diff --git a/mirai-console/backend/mirai-console/src/MiraiConsole.kt b/mirai-console/backend/mirai-console/src/MiraiConsole.kt
index 4d81a849e5..badb9c70d2 100644
--- a/mirai-console/backend/mirai-console/src/MiraiConsole.kt
+++ b/mirai-console/backend/mirai-console/src/MiraiConsole.kt
@@ -34,7 +34,7 @@ import net.mamoe.mirai.console.util.ConsoleInternalApi
 import net.mamoe.mirai.console.util.SemVersion
 import net.mamoe.mirai.utils.*
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import java.time.Instant
 
 /**
diff --git a/mirai-console/backend/mirai-console/src/MiraiConsoleImplementation.kt b/mirai-console/backend/mirai-console/src/MiraiConsoleImplementation.kt
index 751a3884a7..c8466c2e39 100644
--- a/mirai-console/backend/mirai-console/src/MiraiConsoleImplementation.kt
+++ b/mirai-console/backend/mirai-console/src/MiraiConsoleImplementation.kt
@@ -40,7 +40,7 @@ import net.mamoe.mirai.console.util.ConsoleInput
 import net.mamoe.mirai.console.util.ConsoleInternalApi
 import net.mamoe.mirai.message.data.Message
 import net.mamoe.mirai.utils.*
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import java.util.*
 import java.util.concurrent.locks.ReentrantLock
 import kotlin.annotation.AnnotationTarget.*
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/AccessDeniedException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/AccessDeniedException.java
new file mode 100644
index 0000000000..97eed5f360
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/AccessDeniedException.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class AccessDeniedException extends FileSystemException {
+
+  public AccessDeniedException (String file) {
+    super(file);
+  }
+
+  public AccessDeniedException (String file, String otherFile, String reason) {
+    super(file, otherFile, reason);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/AtomicMoveNotSupportedException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/AtomicMoveNotSupportedException.java
new file mode 100644
index 0000000000..defa48873b
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/AtomicMoveNotSupportedException.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class AtomicMoveNotSupportedException extends FileSystemException {
+
+  public AtomicMoveNotSupportedException (String source, String target, String reason) {
+    super(source, target, reason);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/ClosedFileSystemException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ClosedFileSystemException.java
new file mode 100644
index 0000000000..14ba84d3a6
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ClosedFileSystemException.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class ClosedFileSystemException extends IllegalStateException {
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/ClosedWatchServiceException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ClosedWatchServiceException.java
new file mode 100644
index 0000000000..03bfa50216
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ClosedWatchServiceException.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class ClosedWatchServiceException extends IllegalStateException {}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/CopyOption.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/CopyOption.java
new file mode 100644
index 0000000000..e9413ef679
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/CopyOption.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public interface CopyOption {
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryIteratorException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryIteratorException.java
new file mode 100644
index 0000000000..f37b33a716
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryIteratorException.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.IOException;
+import java.util.ConcurrentModificationException;
+
+@SuppressWarnings("serial")
+public class DirectoryIteratorException extends ConcurrentModificationException {
+
+  public DirectoryIteratorException (IOException cause) {
+    initCause(cause);
+  }
+
+  @Override
+  public final IOException getCause () {
+    return (IOException)super.getCause();
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryNotEmptyException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryNotEmptyException.java
new file mode 100644
index 0000000000..7ac91fe0b9
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryNotEmptyException.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class DirectoryNotEmptyException extends FileSystemException {
+
+  public DirectoryNotEmptyException (String file) {
+    super(file);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryStream.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryStream.java
new file mode 100644
index 0000000000..ffe8a78ffc
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/DirectoryStream.java
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.Closeable;
+import java.io.IOException;
+
+public interface DirectoryStream<T> extends Iterable<T>, Closeable {
+  public interface Filter<T> {
+    public boolean accept (T entry) throws IOException;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileAlreadyExistsException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileAlreadyExistsException.java
new file mode 100644
index 0000000000..53667a6e31
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileAlreadyExistsException.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class FileAlreadyExistsException extends FileSystemException {
+
+  public FileAlreadyExistsException (String file) {
+    super(file);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileStore.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileStore.java
new file mode 100644
index 0000000000..787024cb2d
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileStore.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.IOException;
+
+public abstract class FileStore {
+  protected FileStore () {}
+  public abstract String name ();
+  public abstract String type ();
+  public abstract boolean isReadOnly ();
+  public abstract long getTotalSpace () throws IOException;
+  public abstract long getUsableSpace () throws IOException;
+  public abstract long getUnallocatedSpace () throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystem.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystem.java
new file mode 100644
index 0000000000..b6782f73d2
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystem.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.attribute.UserPrincipalLookupService;
+import com.llamalab.safs.spi.FileSystemProvider;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.Set;
+
+public abstract class FileSystem implements Closeable {
+  public abstract FileSystemProvider provider ();
+  public abstract boolean isOpen ();
+  public abstract boolean isReadOnly ();
+  public abstract Set<String> supportedFileAttributeViews();
+  public abstract String getSeparator ();
+  public abstract Path getPath (String first, String... more);
+  public abstract PathMatcher getPathMatcher (String syntaxAndPattern);
+  public abstract Iterable<FileStore> getFileStores ();
+  public abstract Iterable<Path> getRootDirectories ();
+  public abstract UserPrincipalLookupService getUserPrincipalLookupService ();
+  public abstract WatchService newWatchService () throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemAlreadyExistsException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemAlreadyExistsException.java
new file mode 100644
index 0000000000..c1d319a667
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemAlreadyExistsException.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class FileSystemAlreadyExistsException extends RuntimeException {
+
+  public FileSystemAlreadyExistsException () {}
+
+  public FileSystemAlreadyExistsException (String message) {
+    super(message);
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemException.java
new file mode 100644
index 0000000000..c677dfee52
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemException.java
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.IOException;
+
+@SuppressWarnings("serial")
+public class FileSystemException extends IOException {
+
+  private final String file;
+  private final String otherFile;
+
+  public FileSystemException (String file) {
+    this(file, null, null);
+  }
+
+  public FileSystemException (String file, String otherFile, String reason) {
+    super(reason);
+    this.file = file;
+    this.otherFile = otherFile;
+  }
+
+  public String getFile () {
+    return file;
+  }
+
+  public String getOtherFile () {
+    return otherFile;
+  }
+
+  public String getReason () {
+    return super.getMessage();
+  }
+
+  @Override
+  public String getMessage() {
+    if (file == null && otherFile == null)
+      return getReason();
+    final StringBuilder sb = new StringBuilder();
+    if (file != null)
+      sb.append(file);
+    if (otherFile != null)
+      sb.append(" -> ").append(otherFile);
+    if (getReason() != null)
+      sb.append(": ").append(getReason());
+    return sb.toString();
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemLoopException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemLoopException.java
new file mode 100644
index 0000000000..5cd59e3bc4
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemLoopException.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class FileSystemLoopException extends FileSystemException {
+
+  public FileSystemLoopException (String file) {
+    super(file);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemNotFoundException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemNotFoundException.java
new file mode 100644
index 0000000000..962e589aa8
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystemNotFoundException.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class FileSystemNotFoundException extends RuntimeException {
+
+  public FileSystemNotFoundException () {}
+
+  public FileSystemNotFoundException (String message) {
+    super(message);
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystems.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystems.java
new file mode 100644
index 0000000000..ed5c0724bf
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileSystems.java
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.java.DefaultJavaFileSystemProvider;
+import com.llamalab.safs.spi.FileSystemProvider;
+
+import java.io.IOException;
+import java.net.URI;
+import java.util.Map;
+
+public final class FileSystems {
+
+  private FileSystems () {}
+
+  public static FileSystem getDefault () {
+    return DefaultFileSystemHolder.fileSystem;
+  }
+
+  public static FileSystem getFileSystem (URI uri) {
+    for (final FileSystemProvider provider : FileSystemProvider.installedProviders()) {
+      if (provider.getScheme().equalsIgnoreCase(uri.getScheme()))
+        return provider.getFileSystem(uri);
+    }
+    throw new ProviderNotFoundException(uri.getScheme());
+  }
+
+  public static FileSystem newFileSystem (URI uri, Map<String,?> env) throws IOException {
+    for (final FileSystemProvider provider : FileSystemProvider.installedProviders()) {
+      if (provider.getScheme().equalsIgnoreCase(uri.getScheme()))
+        return provider.newFileSystem(uri, env);
+    }
+    throw new ProviderNotFoundException(uri.getScheme());
+  }
+
+
+  private static final class DefaultFileSystemHolder {
+
+    static final FileSystem fileSystem = loadDefaultProvider().getFileSystem(URI.create("file:///"));
+
+    private static FileSystemProvider loadDefaultProvider () {
+      FileSystemProvider provider = new DefaultJavaFileSystemProvider();
+      final String value = System.getProperty("com.llamalab.safs.spi.DefaultFileSystemProvider");
+      if (value != null) {
+        try {
+          for (final String className : value.split(",")) {
+            provider = (FileSystemProvider)Class.forName(className)
+                .getDeclaredConstructor(FileSystemProvider.class)
+                .newInstance(provider);
+          }
+        }
+        catch (Throwable t) {
+          throw new Error(t);
+        }
+      }
+      return provider;
+    }
+
+  } // class DefaultFileSystemHolder
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitOption.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitOption.java
new file mode 100644
index 0000000000..1ddef8a490
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitOption.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public enum FileVisitOption {
+  /** Follow symbolic links. */
+  FOLLOW_LINKS,
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitResult.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitResult.java
new file mode 100644
index 0000000000..82d42f113a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitResult.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public enum FileVisitResult {
+  CONTINUE,
+  TERMINATE,
+  SKIP_SUBTREE,
+  SKIP_SIBLINGS,
+}
\ No newline at end of file
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitor.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitor.java
new file mode 100644
index 0000000000..c385e7ee45
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/FileVisitor.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.attribute.BasicFileAttributes;
+
+import java.io.IOException;
+
+public interface FileVisitor<T> {
+  public FileVisitResult preVisitDirectory (T dir, BasicFileAttributes attrs) throws IOException;
+  public FileVisitResult postVisitDirectory (T dir, IOException e) throws IOException;
+  public FileVisitResult visitFile (T file, BasicFileAttributes attrs) throws IOException;
+  public FileVisitResult visitFileFailed (T file, IOException e) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/Files.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Files.java
new file mode 100644
index 0000000000..ccbcf50b00
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Files.java
@@ -0,0 +1,630 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.attribute.BasicFileAttributes;
+import com.llamalab.safs.attribute.FileAttribute;
+import com.llamalab.safs.attribute.FileAttributeView;
+import com.llamalab.safs.attribute.FileTime;
+import com.llamalab.safs.internal.BasicFileAttribute;
+import com.llamalab.safs.internal.DefaultFileSystem;
+import com.llamalab.safs.internal.SearchSet;
+import com.llamalab.safs.internal.Utils;
+import com.llamalab.safs.channels.SeekableByteChannel;
+import com.llamalab.safs.spi.FileSystemProvider;
+import com.llamalab.safs.spi.FileTypeDetector;
+import org.apache.commons.lang3.NotImplementedException;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.*;
+import java.net.URLConnection;
+import java.nio.charset.Charset;
+import java.security.SecureRandom;
+import java.util.ArrayList;
+import java.util.EnumSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.ServiceLoader;
+import java.util.Set;
+
+public final class Files {
+
+  //private static final OpenOption[] COPY_REPLACE_EXISTING = { StandardOpenOption.WRITE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.CREATE };
+  //private static final OpenOption[] COPY_KEEP_EXISTING = { StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW };
+  private static final LinkOption[] LINK_NOFOLLOW_LINKS = { LinkOption.NOFOLLOW_LINKS };
+  private static final Set<FileVisitOption> VISIT_EMPTY = EnumSet.noneOf(FileVisitOption.class);
+
+  private static final String COPIED_ATTRIBUTES = BasicFileAttribute.lastModifiedTime + "," + BasicFileAttribute.lastAccessTime + "," + BasicFileAttribute.creationTime;
+
+  private static final SecureRandom TEMP_RAND = new SecureRandom();
+
+  private Files () {}
+
+  public static FileStore getFileStore (Path path) throws IOException {
+    return provider(path).getFileStore(path);
+  }
+
+  public static void delete (Path path) throws IOException {
+    provider(path).delete(path);
+  }
+
+  private static void deleteQuietly (Path path) {
+    try {
+      delete(path);
+    }
+    catch (Throwable t) {
+      // ignore
+    }
+  }
+  public static boolean deleteIfExists (Path path) throws IOException {
+    return provider(path).deleteIfExists(path);
+  }
+
+  public static Path createDirectory (Path dir, FileAttribute<?>... attrs) throws IOException {
+    provider(dir).createDirectory(dir, attrs);
+    return dir;
+  }
+
+  public static Path createDirectories (Path dir, FileAttribute<?>... attrs) throws IOException {
+    final FileSystemProvider provider = provider(dir);
+    try {
+      provider.createDirectory(dir, attrs);
+      return dir;
+    }
+    catch (FileAlreadyExistsException e) {
+      if (Files.isDirectory(dir))
+        return dir;
+      throw e;
+    }
+    catch (Exception e) {
+      // ignore
+    }
+    final Path absolute = dir.toAbsolutePath();
+    Path parent = absolute.getParent();
+    for (;; parent = parent.getParent()) {
+      if (parent == null)
+        throw new FileSystemException(dir.toString(), null, "No root directory");
+      try {
+        final BasicFileAttributes basic = provider.readAttributes(parent, BasicFileAttributes.class);
+        if (!basic.isDirectory())
+          throw new FileAlreadyExistsException(dir.toString());
+        break;
+      }
+      catch (NoSuchFileException e) {
+        // continue
+      }
+    }
+    Path child = parent;
+    for (final Path name : parent.relativize(absolute))
+      provider.createDirectory(child = child.resolve(name));
+    return dir;
+  }
+
+  public static Path createFile (Path path, FileAttribute<?>... attrs) throws IOException {
+    try {
+      newByteChannel(path, EnumSet.of(StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW), attrs).close();
+    }
+    catch (UnsupportedOperationException e) {
+      if (attrs.length != 0)
+        throw e;
+      newOutputStream(path, StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW).close();
+    }
+    return path;
+  }
+
+  private static Path makeTempPath (Path dir, String prefix, String suffix) {
+    long n = TEMP_RAND.nextLong();
+    if (n == Long.MIN_VALUE)
+      n = 0;
+    else if (n < 0)
+      n *= -1;
+    final Path name = dir.getFileSystem().getPath(prefix + Long.toString(n) + suffix);
+    if (name.getParent() != null)
+      throw new IllegalArgumentException("Invalid prefix or suffix");
+    return dir.resolve(name);
+  }
+
+  public static Path createTempFile (Path dir, String prefix, String suffix, FileAttribute<?>... attrs) throws IOException {
+    if (prefix == null)
+      prefix = "";
+    if (suffix == null)
+      suffix = ".tmp";
+    for (;;) {
+      try {
+        return createFile(makeTempPath(dir, prefix, suffix), attrs);
+      }
+      catch (FileAlreadyExistsException e) {
+        // retry
+      }
+    }
+  }
+
+  public static Path createTempFile (String prefix, String suffix, FileAttribute<?>... attrs) throws IOException {
+    final FileSystem fs = FileSystems.getDefault();
+    if (!(fs instanceof DefaultFileSystem))
+      throw new UnsupportedOperationException();
+    return createTempFile(((DefaultFileSystem)fs).getCacheDirectory(), prefix, suffix, attrs);
+  }
+
+  public static Path createTempDirectory (Path dir, String prefix, FileAttribute<?>... attrs) throws IOException {
+    if (prefix == null)
+      prefix = "";
+    for (;;) {
+      try {
+        return Files.createDirectory(makeTempPath(dir, prefix, ""), attrs);
+      }
+      catch (FileAlreadyExistsException e) {
+        // retry
+      }
+    }
+  }
+
+  public static Path createTempDirectory (String prefix, FileAttribute<?>... attrs) throws IOException {
+    final FileSystem fs = FileSystems.getDefault();
+    if (!(fs instanceof DefaultFileSystem))
+      throw new UnsupportedOperationException();
+    return createTempDirectory(((DefaultFileSystem)fs).getCacheDirectory(), prefix, attrs);
+
+  }
+
+  public static byte[] readAllBytes (Path path) throws IOException {
+    final InputStream in = newInputStream(path);
+    try {
+      final long size = size(path);
+      if (size > Integer.MAX_VALUE)
+        throw new OutOfMemoryError("Array size exceeded");
+      return Utils.readAllBytes(in, (int)size);
+    }
+    finally {
+      in.close();
+    }
+  }
+
+  public static Path write (Path path, byte[] bytes, OpenOption... options) throws IOException {
+    final OutputStream out = newOutputStream(path, options);
+    try {
+      out.write(bytes);
+    }
+    finally {
+      out.close();
+    }
+    return path;
+  }
+
+  /**
+   * Does not delete target upon failure.
+   */
+  public static long copy (InputStream in, Path target, CopyOption... options) throws IOException {
+    if (in == null)
+      throw new NullPointerException("in");
+    for (final CopyOption option : options) {
+      if (StandardCopyOption.REPLACE_EXISTING == option) {
+        deleteIfExists(target);
+        break;
+      }
+    }
+    final OutputStream out = newOutputStream(target, StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW);
+    try {
+      return Utils.transfer(in, out);
+    }
+    finally {
+      out.close();
+    }
+  }
+
+  public static long copy (Path source, OutputStream out) throws IOException {
+    final InputStream in = newInputStream(source);
+    try {
+      return Utils.transfer(in, out);
+    }
+    finally {
+      out.close();
+    }
+  }
+
+  public static Path copy (Path source, Path target, CopyOption... options) throws IOException {
+    return transfer(source, target, false, options);
+  }
+
+  public static Path move (Path source, Path target, CopyOption... options) throws IOException {
+    return transfer(source, target, true, options);
+  }
+
+  private static Path transfer (Path source, Path target, boolean move, CopyOption[] options) throws IOException {
+    final FileSystemProvider provider = provider(source);
+    if (provider == provider(target)) {
+      if (move)
+        provider.move(source, target, options);
+      else
+        provider.copy(source, target, options);
+      return target;
+    }
+    boolean replaceExisting = false;
+    boolean copyAttributes = false;
+    LinkOption[] linkOptions = Utils.EMPTY_LINK_OPTION_ARRAY;
+    for (final CopyOption option : options) {
+      if (StandardCopyOption.REPLACE_EXISTING == option)
+        replaceExisting = true;
+      else if (StandardCopyOption.COPY_ATTRIBUTES == option)
+        copyAttributes = true;
+      else if (LinkOption.NOFOLLOW_LINKS == option)
+        linkOptions = LINK_NOFOLLOW_LINKS;
+      else if (StandardCopyOption.ATOMIC_MOVE == option && move)
+        throw new AtomicMoveNotSupportedException(source.toString(), target.toString(), "Different providers");
+    }
+    if (replaceExisting)
+      deleteIfExists(target);
+    if (isDirectory(source))
+      createDirectory(target);
+    else {
+      final InputStream in = newInputStream(source);
+      try {
+        final OutputStream out = newOutputStream(target, StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW);
+        try {
+          Utils.transfer(in, out);
+        }
+        finally {
+          out.close();
+        }
+      }
+      finally {
+        in.close();
+      }
+    }
+    try {
+      if (copyAttributes) {
+        for (final Map.Entry<String, Object> attr : readAttributes(source, COPIED_ATTRIBUTES, linkOptions).entrySet()) {
+          try {
+            setAttribute(target, attr.getKey(), attr.getValue());
+          }
+          catch (UnsupportedOperationException e) {
+            // suppressed
+          }
+        }
+      }
+      if (move)
+        delete(source);
+    }
+    catch (IOException e) {
+      deleteQuietly(target);
+      throw e;
+    }
+    catch (RuntimeException e) {
+      deleteQuietly(target);
+      throw e;
+    }
+    return target;
+  }
+
+  public static SeekableByteChannel newByteChannel(Path path, OpenOption... options) throws IOException {
+    return provider(path).newByteChannel(path, new SearchSet<OpenOption>(options));
+  }
+
+  public static SeekableByteChannel newByteChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs) throws IOException {
+    return provider(path).newByteChannel(path, options, attrs);
+  }
+
+  public static InputStream newInputStream (Path path, OpenOption...options) throws IOException {
+    return provider(path).newInputStream(path);
+  }
+
+  public static OutputStream newOutputStream (Path path, OpenOption...options) throws IOException {
+    return provider(path).newOutputStream(path, options);
+  }
+
+  public static BufferedReader newBufferedReader (Path path) throws IOException {
+    return newBufferedReader(path, Utils.UTF_8);
+  }
+
+  public static BufferedReader newBufferedReader (Path path, Charset charset) throws IOException {
+    return new BufferedReader(new InputStreamReader(newInputStream(path), charset));
+  }
+
+  public static BufferedWriter newBufferedWriter (Path path, OpenOption... options) throws IOException {
+    return newBufferedWriter(path, Utils.UTF_8, options);
+  }
+
+  public static BufferedWriter newBufferedWriter (Path path, Charset charset, OpenOption... options) throws IOException {
+    return new BufferedWriter(new OutputStreamWriter(newOutputStream(path, options), charset));
+  }
+
+  public static boolean exists (Path path, LinkOption... options) {
+    try {
+      readAttributes(path, BasicFileAttributes.class, options);
+      return true;
+    }
+    catch (IOException e) {
+      return false;
+    }
+  }
+
+  public static boolean notExists (Path path, LinkOption... options) {
+    try {
+      readAttributes(path, BasicFileAttributes.class, options);
+      return false;
+    }
+    catch (NoSuchFileException e) {
+      return true;
+    }
+    catch (IOException e) {
+      return false;
+    }
+  }
+
+  public static boolean isSameFile (Path path1, Path path2) throws IOException {
+    final FileSystem fs = path1.getFileSystem();
+    return fs.equals(path2.getFileSystem())
+        && fs.provider().isSameFile(path1, path2);
+  }
+
+  public static boolean isHidden (Path path) throws IOException {
+    return provider(path).isHidden(path);
+  }
+
+  public static boolean isDirectory (Path path, LinkOption... options) {
+    try {
+      return readAttributes(path, BasicFileAttributes.class, options).isDirectory();
+    }
+    catch (IOException e) {
+      return false;
+    }
+  }
+
+  public static boolean isRegularFile (Path path, LinkOption... options) {
+    try {
+      return readAttributes(path, BasicFileAttributes.class, options).isRegularFile();
+    }
+    catch (IOException e) {
+      return false;
+    }
+  }
+
+  public static boolean isSymbolicLink (Path path) {
+    try {
+      readSymbolicLink(path);
+      return true;
+    }
+    catch (IOException e) {
+      return false;
+    }
+  }
+
+  public static long size (Path path) throws IOException {
+    return readAttributes(path, BasicFileAttributes.class).size();
+  }
+
+  public static FileTime getLastModifiedTime (Path path, LinkOption... options) throws IOException {
+    return readAttributes(path, BasicFileAttributes.class, options).lastModifiedTime();
+  }
+
+  public static Path setLastModifiedTime (Path path, FileTime time) throws IOException {
+    return setAttribute(path, BasicFileAttribute.lastModifiedTime.toString(), time);
+  }
+
+  public static Path readSymbolicLink (Path link) throws IOException {
+    return provider(link).readSymbolicLink(link);
+  }
+
+  public static <A extends BasicFileAttributes> A readAttributes (Path path, Class<A> type, LinkOption... options) throws IOException {
+    return provider(path).readAttributes(path, type, options);
+  }
+
+  public static Map<String,Object> readAttributes (Path path, String attributes, LinkOption... options) throws IOException {
+    return provider(path).readAttributes(path, attributes, options);
+  }
+
+  public static Path setAttribute (Path path, String attribute, Object value, LinkOption... options) throws IOException {
+    provider(path).setAttribute(path, attribute, value, options);
+    return path;
+  }
+
+  public static <V extends FileAttributeView> V getFileAttributeView (Path path, Class<V> type, LinkOption... options) {
+    return provider(path).getFileAttributeView(path, type, options);
+  }
+
+  public static String probeContentType (Path path) throws IOException {
+    for (final FileTypeDetector detector : InstalledFileTypeDetectorsHolder.detectors) {
+      final String type = detector.probeContentType(path);
+      if (type != null)
+        return type;
+    }
+    return null;
+  }
+
+  public static DirectoryStream<Path> newDirectoryStream (Path dir) throws IOException{
+    return newDirectoryStream(dir, Utils.ACCEPT_ALL_FILTER);
+  }
+
+  public static DirectoryStream<Path> newDirectoryStream (Path dir, String glob) throws IOException {
+    if ("*".equals(glob))
+      return newDirectoryStream(dir);
+    final PathMatcher matcher = dir.getFileSystem().getPathMatcher("glob:"+glob);
+    //noinspection RedundantThrows
+    return newDirectoryStream(dir, new DirectoryStream.Filter<Path>() {
+      @Override
+      public boolean accept (Path entry) throws IOException {
+        return matcher.matches(entry.getFileName());
+      }
+    });
+  }
+
+  public static DirectoryStream<Path> newDirectoryStream (Path dir, DirectoryStream.Filter<? super Path> filter) throws IOException{
+    return provider(dir).newDirectoryStream(dir, filter);
+  }
+
+  public static Path walkFileTree (Path start, FileVisitor<? super Path> visitor) throws IOException {
+    return walkFileTree(start, VISIT_EMPTY, Integer.MAX_VALUE, visitor);
+  }
+
+  @SuppressWarnings("ConstantConditions")
+  public static Path walkFileTree (Path start, Set<FileVisitOption> options, int maxDepth, FileVisitor<? super Path> visitor) throws IOException {
+    final boolean followLinks = options.contains(FileVisitOption.FOLLOW_LINKS);
+    final LinkOption[] linkOptions = followLinks ? Utils.EMPTY_LINK_OPTION_ARRAY : LINK_NOFOLLOW_LINKS;
+    WalkDirectory dir = null;
+    try {
+      Path path = start;
+      FileVisitResult result;
+      int depth = 0;
+      walk: do {
+
+        // iterate
+        while (dir != null) {
+          IOException cause = null;
+          try {
+            if (dir.iterator.hasNext()) {
+              path = dir.iterator.next();
+              break;
+            }
+          }
+          catch (DirectoryIteratorException e) {
+            cause = e.getCause();
+          }
+          if (FileVisitResult.TERMINATE == visitor.postVisitDirectory(dir.path, cause) || --depth <= 0)
+            break walk;
+          Utils.closeQuietly(dir.stream);
+          dir = dir.parent;
+        }
+
+        // descend
+        DirectoryStream<Path> stream = null;
+        BasicFileAttributes attrs = null;
+        try {
+          attrs = readAttributes(path, BasicFileAttributes.class, linkOptions);
+          if (attrs.isDirectory() && depth < maxDepth) {
+            if (followLinks) {
+              // check for recursion
+              for (WalkDirectory ancestor = dir; ancestor != null; ancestor = ancestor.parent) {
+                if (ancestor.isSameFile(path, attrs.fileKey()))
+                  throw new FileSystemLoopException(path.toString());
+              }
+            }
+            stream = Files.newDirectoryStream(path);
+          }
+        }
+        catch (NotDirectoryException e) {
+          // visitFile below
+        }
+        catch (IOException e) {
+          result = visitor.visitFileFailed(path, e);
+          if (FileVisitResult.SKIP_SIBLINGS == result && dir != null)
+            dir.iterator = Utils.emptyIterator();
+          continue;
+        }
+        if (stream != null) {
+          result = visitor.preVisitDirectory(path, attrs);
+          if (FileVisitResult.CONTINUE == result) {
+            dir = new WalkDirectory(dir, path, attrs.fileKey(), stream);
+            ++depth;
+          }
+          else
+            Utils.closeQuietly(stream);
+        }
+        else {
+          result = visitor.visitFile(path, attrs);
+          if (FileVisitResult.SKIP_SIBLINGS == result && dir != null)
+            dir.iterator = Utils.emptyIterator();
+        }
+      } while (FileVisitResult.TERMINATE != result && depth > 0);
+    }
+    finally {
+      for (; dir != null; dir = dir.parent)
+        Utils.closeQuietly(dir.stream);
+    }
+    return start;
+  }
+
+
+    public static File[] walk(@Nullable Path path) {
+        throw new NotImplementedException("我懒得写");
+    }
+
+
+    private static final class WalkDirectory {
+
+    public final WalkDirectory parent;
+    public final Path path;
+    public final Object key;
+    public final DirectoryStream<Path> stream;
+    public Iterator<Path> iterator;
+
+    public WalkDirectory (WalkDirectory parent, Path path, Object key, DirectoryStream<Path> stream) {
+      this.parent = parent;
+      this.path = path;
+      this.key = key;
+      this.stream = stream;
+      this.iterator = stream.iterator();
+    }
+
+    public boolean isSameFile (Path path, Object key) {
+      if (key != null && this.key != null)
+        return key.equals(this.key);
+      try {
+        return Files.isSameFile(path, this.path);
+      }
+      catch (IOException e) {
+        return false;
+      }
+    }
+
+  } // class WalkDirectory
+
+
+  private static FileSystemProvider provider (Path path) {
+    return path.getFileSystem().provider();
+  }
+
+
+  private static final class InstalledFileTypeDetectorsHolder {
+
+    private static final List<FileTypeDetector> detectors = loadInstalledProviders();
+
+    private static List<FileTypeDetector> loadInstalledProviders () {
+      final List<FileTypeDetector> detectors = new ArrayList<FileTypeDetector>();
+      for (final FileTypeDetector detector : ServiceLoader.load(FileTypeDetector.class, FileTypeDetector.class.getClassLoader()))
+        detectors.add(detector);
+      //noinspection RedundantThrows
+      detectors.add(new FileTypeDetector() {
+        private final boolean apacheHarmony = isApacheHarmony();
+        @Override
+        public String probeContentType (Path path) throws IOException {
+          // TODO: Use URLConnection.guessContentTypeFromStream()
+          String filename = path.toString();
+          // BUG: https://code.google.com/p/android/issues/detail?id=162883
+          // https://android.googlesource.com/platform/libcore/+/marshmallow-release/luni/src/main/java/java/net/DefaultFileNameMap.java
+          if (apacheHarmony)
+            filename = filename.replace('#', '_');
+          return URLConnection.guessContentTypeFromName(filename);
+        }
+      });
+      return detectors;
+    }
+
+    private static boolean isApacheHarmony () {
+      try {
+        Class.forName("libcore.net.MimeUtils", false, InstalledFileTypeDetectorsHolder.class.getClassLoader());
+        return true;
+      }
+      catch (ClassNotFoundException e) {
+        return false;
+      }
+    }
+
+  } // class InstalledFileTypeDetectorsHolder
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/InvalidPathException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/InvalidPathException.java
new file mode 100644
index 0000000000..4bd781ea1f
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/InvalidPathException.java
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class InvalidPathException extends IllegalArgumentException {
+
+  private final String input;
+  private final int index;
+
+  public InvalidPathException (String input, String reason) {
+    this(input, reason, -1);
+  }
+
+  public InvalidPathException (String input, String reason, int index) {
+    super(reason);
+    this.input = input;
+    this.index = index;
+  }
+
+  public String getInput () {
+    return input;
+  }
+
+  public String getReason () {
+    return super.getMessage();
+  }
+
+  public int getIndex () {
+    return index;
+  }
+
+  @Override
+  public String getMessage () {
+    final StringBuilder sb = new StringBuilder().append(getReason());
+    if (index >= 0)
+      sb.append(" at index ").append(index);
+    return sb.append(": ").append(input).toString();
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/LinkOption.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/LinkOption.java
new file mode 100644
index 0000000000..4c7a0659ae
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/LinkOption.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public enum LinkOption implements OpenOption, CopyOption {
+  /** Do not follow symbolic links. */
+  NOFOLLOW_LINKS,
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/NoSuchFileException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/NoSuchFileException.java
new file mode 100644
index 0000000000..adeb9bd4e0
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/NoSuchFileException.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class NoSuchFileException extends FileSystemException {
+
+  public NoSuchFileException (String file) {
+    super(file);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/NotDirectoryException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/NotDirectoryException.java
new file mode 100644
index 0000000000..a8567ef0c1
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/NotDirectoryException.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class NotDirectoryException extends FileSystemException {
+
+  public NotDirectoryException (String file) {
+    super(file);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/NotLinkException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/NotLinkException.java
new file mode 100644
index 0000000000..d223dac2bb
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/NotLinkException.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class NotLinkException extends FileSystemException {
+
+  public NotLinkException (String file) {
+    super(file);
+  }
+
+  public NotLinkException (String file, String otherFile, String reason) {
+    super(file, otherFile, reason);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/OpenOption.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/OpenOption.java
new file mode 100644
index 0000000000..3fc183218c
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/OpenOption.java
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public interface OpenOption {}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/Path.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Path.java
new file mode 100644
index 0000000000..b1a7073b04
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Path.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.URI;
+
+public interface Path extends Comparable<Path>, Iterable<Path>, Watchable {
+  public FileSystem getFileSystem ();
+
+  public boolean isAbsolute ();
+  public Path getRoot ();
+  public Path getParent ();
+  public Path getFileName ();
+  public int getNameCount ();
+  public Path getName (int index);
+  public Path subpath (int beginIndex, int endIndex);
+  public boolean startsWith (Path other);
+  public boolean startsWith (String other);
+  public boolean endsWith (Path other);
+  public boolean endsWith (String other);
+
+  public Path normalize ();
+  public Path relativize (Path other);
+  public Path resolve (Path other);
+  public Path resolve (String other);
+  public Path resolveSibling (Path other);
+  public Path resolveSibling (String other);
+
+  public Path toAbsolutePath ();
+  public Path toRealPath (LinkOption... options) throws IOException;
+  public File toFile ();
+  public URI toUri ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/PathMatcher.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/PathMatcher.java
new file mode 100644
index 0000000000..6d2d16c490
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/PathMatcher.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public interface PathMatcher {
+  public boolean matches (Path path);
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/Paths.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Paths.java
new file mode 100644
index 0000000000..d349058485
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Paths.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.spi.FileSystemProvider;
+
+import java.io.File;
+import java.net.URI;
+
+public final class Paths {
+
+  private Paths () {}
+
+  public static Path get (String first, String... more) {
+    return FileSystems.getDefault().getPath(first, more);
+  }
+
+  public static Path get (URI uri) {
+    final String scheme =  uri.getScheme();
+    if (scheme == null)
+      throw new IllegalArgumentException("No scheme");
+    for (final FileSystemProvider provider: FileSystemProvider.installedProviders()) {
+      if (scheme.equalsIgnoreCase(provider.getScheme()))
+        return provider.getPath(uri);
+    }
+    throw new FileSystemNotFoundException(scheme);
+  }
+
+  /**
+   * Non-standard. Since we can't add toPath to {@link java.io.File}.
+   */
+  public static Path get (File file) {
+    return get(file.toString());
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/ProviderMismatchException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ProviderMismatchException.java
new file mode 100644
index 0000000000..5f5eed7d16
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ProviderMismatchException.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class ProviderMismatchException extends IllegalArgumentException {
+
+  public ProviderMismatchException () {}
+
+  public ProviderMismatchException (String message) {
+    super(message);
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/ProviderNotFoundException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ProviderNotFoundException.java
new file mode 100644
index 0000000000..6315ce1ab8
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ProviderNotFoundException.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class ProviderNotFoundException extends RuntimeException {
+
+  public ProviderNotFoundException () {}
+
+  public ProviderNotFoundException (String message) {
+    super(message);
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/ReadOnlyFileSystemException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ReadOnlyFileSystemException.java
new file mode 100644
index 0000000000..b61d4e8e3a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/ReadOnlyFileSystemException.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+@SuppressWarnings("serial")
+public class ReadOnlyFileSystemException  extends UnsupportedOperationException {
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/SimpleFileVisitor.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/SimpleFileVisitor.java
new file mode 100644
index 0000000000..9d749fa934
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/SimpleFileVisitor.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.attribute.BasicFileAttributes;
+
+import java.io.IOException;
+
+public class SimpleFileVisitor<T> implements FileVisitor<T> {
+
+  @Override
+  public FileVisitResult preVisitDirectory (T dir, BasicFileAttributes attrs) throws IOException {
+    return FileVisitResult.CONTINUE;
+  }
+
+  @Override
+  public FileVisitResult postVisitDirectory (T dir, IOException e) throws IOException {
+    if (e != null)
+      throw e;
+    return FileVisitResult.CONTINUE;
+  }
+
+  @Override
+  public FileVisitResult visitFile (T file, BasicFileAttributes attrs) throws IOException {
+    return FileVisitResult.CONTINUE;
+  }
+
+  @Override
+  public FileVisitResult visitFileFailed (T file, IOException e) throws IOException {
+    throw e;
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardCopyOption.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardCopyOption.java
new file mode 100644
index 0000000000..3187b672ff
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardCopyOption.java
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public enum StandardCopyOption implements CopyOption {
+  REPLACE_EXISTING,
+  COPY_ATTRIBUTES,
+  ATOMIC_MOVE,
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardOpenOption.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardOpenOption.java
new file mode 100644
index 0000000000..04c147f12a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardOpenOption.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public enum StandardOpenOption implements OpenOption {
+  READ,
+  WRITE,
+  APPEND,
+  TRUNCATE_EXISTING,
+  CREATE,
+  CREATE_NEW,
+  /** Unsupported. */
+  DELETE_ON_CLOSE,
+  SPARSE,
+  SYNC,
+  DSYNC,
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardWatchEventKinds.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardWatchEventKinds.java
new file mode 100644
index 0000000000..2adc8994f2
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/StandardWatchEventKinds.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import com.llamalab.safs.internal.WatchEventKind;
+
+public final class StandardWatchEventKinds {
+
+  public static final WatchEvent.Kind<Object> OVERFLOW   = new WatchEventKind<Object>("OVERFLOW", Object.class);
+  public static final WatchEvent.Kind<Path> ENTRY_CREATE = new WatchEventKind<Path>("ENTRY_CREATE", Path.class);
+  public static final WatchEvent.Kind<Path> ENTRY_DELETE = new WatchEventKind<Path>("ENTRY_DELETE", Path.class);
+  public static final WatchEvent.Kind<Path> ENTRY_MODIFY = new WatchEventKind<Path>("ENTRY_MODIFY", Path.class);
+
+  private StandardWatchEventKinds() {}
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchEvent.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchEvent.java
new file mode 100644
index 0000000000..28295667da
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchEvent.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+public interface WatchEvent<T> {
+
+  public static interface Kind<T> {
+    public String name ();
+    public Class<T> type ();
+  }
+
+  public static interface Modifier {
+    public String name ();
+  }
+
+  public Kind<T> kind ();
+  public T context ();
+  public int count ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchKey.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchKey.java
new file mode 100644
index 0000000000..27c1796779
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchKey.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.util.List;
+
+public interface WatchKey {
+  public Watchable watchable ();
+  public boolean isValid ();
+  public boolean reset ();
+  public void cancel ();
+  public List<WatchEvent<?>> pollEvents ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchService.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchService.java
new file mode 100644
index 0000000000..6f03ed45fa
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/WatchService.java
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.Closeable;
+import java.util.concurrent.TimeUnit;
+
+public interface WatchService extends Closeable {
+  public WatchKey poll ();
+  public WatchKey poll (long timeout, TimeUnit unit) throws InterruptedException;
+  public WatchKey take () throws InterruptedException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/Watchable.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Watchable.java
new file mode 100644
index 0000000000..a7c55288d6
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/Watchable.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs;
+
+import java.io.IOException;
+
+public interface Watchable {
+  public WatchKey register (WatchService service, WatchEvent.Kind<?>[] kinds, WatchEvent.Modifier... modifiers) throws IOException;
+  public WatchKey register (WatchService service, WatchEvent.Kind<?>... kinds) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/AttributeView.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/AttributeView.java
new file mode 100644
index 0000000000..09f5012cfa
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/AttributeView.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+public interface AttributeView {
+  public String name ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/BasicFileAttributeView.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/BasicFileAttributeView.java
new file mode 100644
index 0000000000..edb3490b22
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/BasicFileAttributeView.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.io.IOException;
+
+public interface BasicFileAttributeView extends FileAttributeView {
+  public BasicFileAttributes readAttributes () throws IOException;
+  public void setTimes (FileTime lastModifiedTime, FileTime lastAccessTime, FileTime createTime) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/BasicFileAttributes.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/BasicFileAttributes.java
new file mode 100644
index 0000000000..b362a79003
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/BasicFileAttributes.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+public interface BasicFileAttributes {
+  public Object fileKey ();
+  public boolean isDirectory ();
+  public boolean isOther ();
+  public boolean isRegularFile ();
+  public boolean isSymbolicLink ();
+  public long size ();
+  public FileTime creationTime ();
+  public FileTime lastModifiedTime ();
+  public FileTime	lastAccessTime ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileAttribute.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileAttribute.java
new file mode 100644
index 0000000000..3e6e0a3993
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileAttribute.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+public interface FileAttribute<T> {
+  public String name ();
+  public T value ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileAttributeView.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileAttributeView.java
new file mode 100644
index 0000000000..07295c2d2c
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileAttributeView.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+public interface FileAttributeView extends AttributeView {
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileOwnerAttributeView.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileOwnerAttributeView.java
new file mode 100644
index 0000000000..ddf5bed34a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileOwnerAttributeView.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.io.IOException;
+
+public interface FileOwnerAttributeView extends FileAttributeView {
+  public UserPrincipal getOwner () throws IOException;
+  public void setOwner (UserPrincipal owner) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileTime.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileTime.java
new file mode 100644
index 0000000000..68ecfeaf5e
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/FileTime.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import com.llamalab.safs.internal.Utils;
+
+import java.util.concurrent.TimeUnit;
+
+public final class FileTime implements Comparable<FileTime> {
+
+  private static final FileTime ZERO = new FileTime(0);
+
+  private final long value;
+
+  private FileTime (long value) {
+    this.value = value;
+  }
+
+  /**
+   * YYYY-MM-DDThh:mm:ss[.s+]Z
+   */
+  @Override
+  public String toString () {
+    return Utils.formatRfc3339(value);
+  }
+
+  @Override
+  public int hashCode () {
+    return (int)(value ^ (value >>> 32));
+  }
+
+  @Override
+  public boolean equals (Object obj) {
+    if (this == obj)
+      return true;
+    if (!(obj instanceof FileTime))
+      return false;
+    return value == ((FileTime)obj).value;
+  }
+
+  @Override
+  public int compareTo (FileTime other) {
+    final long lhs = this.value;
+    final long rhs = other.value;
+    //noinspection UseCompareMethod
+    return (lhs < rhs) ? -1 : (lhs == rhs) ? 0 : 1;
+  }
+
+  public long to (TimeUnit unit) {
+    return unit.convert(value, TimeUnit.MILLISECONDS);
+  }
+
+  public long toMillis () {
+    return to(TimeUnit.MILLISECONDS);
+  }
+
+  public static FileTime from (long value, TimeUnit unit) {
+    if (unit == null)
+      throw new NullPointerException("unit");
+    return fromMillis(TimeUnit.MILLISECONDS.convert(value, unit));
+  }
+
+  public static FileTime fromMillis (long value) {
+    return (value != 0) ? new FileTime(value) : ZERO;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/GroupPrincipal.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/GroupPrincipal.java
new file mode 100644
index 0000000000..1d8446c265
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/GroupPrincipal.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+public interface GroupPrincipal extends UserPrincipal {
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFileAttributeView.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFileAttributeView.java
new file mode 100644
index 0000000000..963bfa9362
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFileAttributeView.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.io.IOException;
+import java.util.Set;
+
+public interface PosixFileAttributeView extends BasicFileAttributeView, FileOwnerAttributeView {
+  public void setGroup (GroupPrincipal group) throws IOException;
+  public void setPermissions (Set<PosixFilePermission> perms) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFileAttributes.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFileAttributes.java
new file mode 100644
index 0000000000..ab9bf9c60a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFileAttributes.java
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.util.Set;
+
+public interface PosixFileAttributes extends BasicFileAttributes {
+  public GroupPrincipal group ();
+  public UserPrincipal owner ();
+  public Set<PosixFilePermission> permissions ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFilePermission.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFilePermission.java
new file mode 100644
index 0000000000..a3b36aea75
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFilePermission.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+public enum PosixFilePermission {
+  OWNER_READ,
+  OWNER_WRITE,
+  OWNER_EXECUTE,
+  GROUP_READ,
+  GROUP_WRITE,
+  GROUP_EXECUTE,
+  OTHERS_READ,
+  OTHERS_WRITE,
+  OTHERS_EXECUTE
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFilePermissions.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFilePermissions.java
new file mode 100644
index 0000000000..95b215e7df
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/PosixFilePermissions.java
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import com.llamalab.safs.internal.SearchSet;
+
+import java.util.EnumSet;
+import java.util.Set;
+
+public final class PosixFilePermissions {
+
+  private PosixFilePermissions () {}
+
+  public static String toString (Set<PosixFilePermission> perms) {
+    final StringBuilder sb = new StringBuilder(9);
+    append(sb,
+        perms.contains(PosixFilePermission.OWNER_READ),
+        perms.contains(PosixFilePermission.OWNER_WRITE),
+        perms.contains(PosixFilePermission.OWNER_EXECUTE));
+    append(sb,
+        perms.contains(PosixFilePermission.GROUP_READ),
+        perms.contains(PosixFilePermission.GROUP_WRITE),
+        perms.contains(PosixFilePermission.GROUP_EXECUTE));
+    append(sb,
+        perms.contains(PosixFilePermission.OTHERS_READ),
+        perms.contains(PosixFilePermission.OTHERS_WRITE),
+        perms.contains(PosixFilePermission.OTHERS_EXECUTE));
+    return sb.toString();
+  }
+
+  private static void append (StringBuilder sb, boolean r, boolean w, boolean x) {
+    sb.append(r ? 'r' : '-').append(w ? 'w' : '-').append(x ? 'x' : '-');
+  }
+
+  public static Set<PosixFilePermission> fromString (String mode) {
+    if (mode.length() != 9)
+      throw new IllegalArgumentException();
+    final Set<PosixFilePermission> set = EnumSet.noneOf(PosixFilePermission.class);
+    add(set, mode, 0, 'r', PosixFilePermission.OWNER_READ);
+    add(set, mode, 1, 'w', PosixFilePermission.OWNER_WRITE);
+    add(set, mode, 2, 'x', PosixFilePermission.OWNER_EXECUTE);
+
+    add(set, mode, 3, 'r', PosixFilePermission.GROUP_READ);
+    add(set, mode, 4, 'w', PosixFilePermission.GROUP_WRITE);
+    add(set, mode, 5, 'x', PosixFilePermission.GROUP_EXECUTE);
+
+    add(set, mode, 6, 'r', PosixFilePermission.OTHERS_READ);
+    add(set, mode, 7, 'w', PosixFilePermission.OTHERS_WRITE);
+    add(set, mode, 8, 'x', PosixFilePermission.OTHERS_EXECUTE);
+    return set;
+  }
+
+  private static void add (Set<PosixFilePermission> set, String mode, int index, char flag, PosixFilePermission perm) {
+    final char c = mode.charAt(index);
+    if (flag == c)
+      set.add(perm);
+    else if ('-' != c)
+      throw new IllegalArgumentException();
+  }
+
+  public static FileAttribute<Set<PosixFilePermission>> asFileAttribute (Set<PosixFilePermission> perms) {
+    //noinspection ToArrayCallWithZeroLengthArrayArgument
+    final Set<PosixFilePermission> value = new SearchSet<PosixFilePermission>(perms.toArray(new PosixFilePermission[perms.size()]));
+    return new FileAttribute<Set<PosixFilePermission>>() {
+
+      @Override
+      public String name() {
+        return "posix:permissions";
+      }
+
+      @Override
+      public Set<PosixFilePermission> value () {
+        return value;
+      }
+    };
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipal.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipal.java
new file mode 100644
index 0000000000..f8c888d105
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipal.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.security.Principal;
+
+public interface UserPrincipal extends Principal {
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipalLookupService.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipalLookupService.java
new file mode 100644
index 0000000000..1240c7b33f
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipalLookupService.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.io.IOException;
+
+public abstract class UserPrincipalLookupService {
+
+  protected UserPrincipalLookupService () {}
+
+  public abstract UserPrincipal lookupPrincipalByName (String name) throws IOException;
+  public abstract GroupPrincipal lookupPrincipalByGroupName (String group) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipalNotFoundException.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipalNotFoundException.java
new file mode 100644
index 0000000000..215d1d2948
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/attribute/UserPrincipalNotFoundException.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.attribute;
+
+import java.io.IOException;
+
+public class UserPrincipalNotFoundException extends IOException {
+
+  private final String name;
+
+  public UserPrincipalNotFoundException (String name) {
+    this.name = name;
+  }
+
+  public String getName (){
+    return name;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/channels/SeekableByteChannel.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/channels/SeekableByteChannel.java
new file mode 100644
index 0000000000..7000795caa
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/channels/SeekableByteChannel.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.channels;
+
+import java.io.IOException;
+import java.nio.channels.ByteChannel;
+
+public interface SeekableByteChannel extends ByteChannel {
+  public long position () throws IOException;
+  public SeekableByteChannel position (long newPosition) throws IOException;
+  public long size () throws IOException;
+  public SeekableByteChannel truncate (long size) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractDirectoryStream.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractDirectoryStream.java
new file mode 100644
index 0000000000..932461f059
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractDirectoryStream.java
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.DirectoryIteratorException;
+import com.llamalab.safs.DirectoryStream;
+
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+public abstract class AbstractDirectoryStream<T> implements DirectoryStream<T>, Iterator<T> {
+
+  private T next;
+  private boolean started;
+  private boolean closed;
+
+  /**
+   * Make sure to call super.close();
+   */
+  @Override
+  public final void close () throws IOException {
+    if (!closed) {
+      closed = true;
+      implCloseStream();
+    }
+  }
+
+  protected void implCloseStream () throws IOException {}
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public final Iterator<T> iterator () {
+    if (started)
+      throw new IllegalStateException();
+    started = true;
+    return this;
+  }
+
+  @Override
+  public final boolean hasNext () {
+    if (next != null)
+      return true;
+    if (closed)
+      return false;
+    try {
+      return (next = advance()) != null;
+    }
+    catch (IOException e) {
+      throw new DirectoryIteratorException(e);
+    }
+  }
+
+  @Override
+  public final T next () {
+    if (closed || !hasNext())
+      throw new NoSuchElementException();
+    final T result = next;
+    next = null;
+    return result;
+  }
+
+  @Override
+  public final void remove () {
+    throw new UnsupportedOperationException();
+  }
+
+  protected abstract T advance () throws IOException;
+}
\ No newline at end of file
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractFileSystemProvider.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractFileSystemProvider.java
new file mode 100644
index 0000000000..944383fbee
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractFileSystemProvider.java
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.NoSuchFileException;
+import com.llamalab.safs.OpenOption;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.ProviderMismatchException;
+import com.llamalab.safs.StandardOpenOption;
+import com.llamalab.safs.attribute.BasicFileAttributeView;
+import com.llamalab.safs.attribute.BasicFileAttributes;
+import com.llamalab.safs.attribute.FileAttribute;
+import com.llamalab.safs.attribute.FileAttributeView;
+import com.llamalab.safs.attribute.FileTime;
+import com.llamalab.safs.spi.FileSystemProvider;
+import com.llamalab.safs.unix.UnixPath;
+
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.net.URI;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Only support {@link UnixPath}.
+ */
+public abstract class AbstractFileSystemProvider extends FileSystemProvider {
+
+  protected static final Set<? extends OpenOption> DEFAULT_NEW_INPUT_STREAM_OPTIONS = EnumSet.of(StandardOpenOption.READ);
+  protected static final Set<? extends OpenOption> DEFAULT_NEW_OUTPUT_STREAM_OPTIONS = EnumSet.of(StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
+
+  protected abstract Class<? extends Path> getPathType ();
+
+  protected void checkPath (Path path) {
+    if (!getPathType().isInstance(path))
+      throw (path == null) ? new NullPointerException() : new ProviderMismatchException();
+    if (path.getFileSystem().provider() != this)
+      throw new ProviderMismatchException();
+  }
+
+  protected void checkUri (URI uri) {
+    if (!getScheme().equalsIgnoreCase(uri.getScheme()))
+      throw new ProviderMismatchException();
+  }
+
+  protected IOException toProperException (IOException ioe, String file, String otherFile) {
+    return (ioe instanceof FileNotFoundException) ? new NoSuchFileException(file) : ioe;
+  }
+
+  @Override
+  public Map<String, Object> readAttributes (Path path, String attributes, LinkOption... options) throws IOException {
+    final Map<String, Object> map = new HashMap<String, Object>();
+    BasicFileAttributes basic = null;
+    for (final BasicFileAttribute attribute : BasicFileAttribute.parse(attributes)) {
+      if (basic == null)
+        basic = readAttributes(path, BasicFileAttributes.class, options); // read once
+      map.put(attribute.toString(), attribute.valueOf(basic));
+    }
+    return map;
+  }
+
+  @Override
+  public void setAttribute (Path path, String attribute, Object value, LinkOption... options) throws IOException {
+    String viewName = BasicFileAttribute.VIEW_NAME;
+    final int colon = attribute.indexOf(':');
+    if (colon != -1) {
+      viewName = attribute.substring(0, colon);
+      attribute = attribute.substring(colon + 1);
+    }
+    final FileAttribute<?> attr = newFileAttribute(viewName, attribute, value);
+    setAttributes(path, Collections.singleton(attr), options);
+  }
+
+  protected FileAttribute<?> newFileAttribute (String viewName, String attribute, Object value) {
+    if (BasicFileAttribute.VIEW_NAME.equals(viewName))
+      return BasicFileAttribute.valueOf(attribute).newFileAttribute(value);
+    throw new UnsupportedOperationException("Attribute: "+viewName+":"+attribute);
+  }
+
+  protected abstract void setAttributes (Path path, Set<? extends FileAttribute<?>> attrs, LinkOption... options) throws IOException;
+
+  @SuppressWarnings("unchecked")
+  public <V extends FileAttributeView> V getFileAttributeView (final Path path, Class<V> type, final LinkOption... options) {
+    checkPath(path);
+    if (BasicFileAttributeView.class == type)
+      return (V)new BasicFileAttributeViewImpl(path, options);
+    return null;
+  }
+
+
+  protected class BasicFileAttributeViewImpl implements BasicFileAttributeView {
+
+    protected final Path path;
+    protected final LinkOption[] options;
+
+    public BasicFileAttributeViewImpl (Path path, LinkOption[] options) {
+      this.path = path;
+      this.options = options;
+    }
+
+    @Override
+    public String name () {
+      return BasicFileAttribute.VIEW_NAME;
+    }
+
+    @Override
+    public BasicFileAttributes readAttributes () throws IOException {
+      return AbstractFileSystemProvider.this.readAttributes(path, BasicFileAttributes.class, options);
+    }
+
+    @Override
+    public void setTimes (FileTime lastModifiedTime, FileTime lastAccessTime, FileTime creationTime) throws IOException {
+      final Set<FileAttribute<?>> attrs = new HashSet<FileAttribute<?>>();
+      if (lastModifiedTime != null)
+        attrs.add(BasicFileAttribute.lastModifiedTime.newFileAttribute(lastModifiedTime));
+      if (lastAccessTime != null)
+        attrs.add(BasicFileAttribute.lastAccessTime.newFileAttribute(lastAccessTime));
+      if (creationTime != null)
+        attrs.add(BasicFileAttribute.creationTime.newFileAttribute(creationTime));
+      AbstractFileSystemProvider.this.setAttributes(path, attrs, options);
+    }
+
+  } // class BasicFileAttributeViewImpl
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractWatchKey.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractWatchKey.java
new file mode 100644
index 0000000000..44a55c0195
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractWatchKey.java
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.StandardWatchEventKinds;
+import com.llamalab.safs.WatchEvent;
+import com.llamalab.safs.WatchKey;
+import com.llamalab.safs.Watchable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public abstract class AbstractWatchKey implements WatchKey {
+
+  private enum State {
+    READY,
+    SIGNALLED,
+  }
+  private final Object eventLock = new Object();
+  private final AbstractWatchService service;
+  private final Watchable watchable;
+  private final int overflowLimit;
+  private List<WatchEvent<?>> events = new ArrayList<WatchEvent<?>>();
+  private State state = State.READY;
+
+  public AbstractWatchKey (AbstractWatchService service, Watchable watchable, int overflowLimit) {
+    this.service = service;
+    this.watchable = watchable;
+    this.overflowLimit = overflowLimit;
+  }
+
+  public final AbstractWatchService service () {
+    return service;
+  }
+
+  @Override
+  public final Watchable watchable () {
+    return watchable;
+  }
+
+  @Override
+  public boolean isValid () {
+    return service.isOpen();
+  }
+
+  @Override
+  public final boolean reset () {
+    synchronized (eventLock) {
+      if (!isValid())
+        return false;
+      if (State.SIGNALLED == state) {
+        if (events.isEmpty())
+          state = State.READY;
+        else
+          service.offer(this);
+      }
+      return true;
+    }
+  }
+
+  @Override
+  public final List<WatchEvent<?>> pollEvents () {
+    synchronized (eventLock) {
+      final List<WatchEvent<?>> result = events;
+      events = new ArrayList<WatchEvent<?>>();
+      return result;
+    }
+  }
+
+  protected final <T> void signalEvent (WatchEvent.Kind<T> kind, T context) {
+    synchronized (eventLock) {
+      final int size = events.size();
+      if (size > 0) {
+        final Event<?> event = (Event<?>)events.get(size - 1);
+        if (   StandardWatchEventKinds.OVERFLOW == event.kind
+            || (event.kind == kind && Utils.equals(event.context, context))) {
+          ++event.count;
+          return;
+        }
+      }
+      if (size < overflowLimit)
+        events.add(new Event<T>(kind, context));
+      else
+        events.add(new Event<Object>(StandardWatchEventKinds.OVERFLOW, null));
+      if (State.READY == state) {
+        state = State.SIGNALLED;
+        service.offer(this);
+      }
+    }
+  }
+
+  private static final class Event<T> implements WatchEvent<T> {
+
+    private final WatchEvent.Kind<T> kind;
+    private final T context;
+    private int count = 1;
+
+    public Event (WatchEvent.Kind<T> kind, T context) {
+      this.kind = kind;
+      this.context = context;
+    }
+
+    @Override
+    public Kind<T> kind () {
+      return kind;
+    }
+
+    @Override
+    public T context () {
+      return context;
+    }
+
+    @Override
+    public int count () {
+      return count;
+    }
+
+    @Override
+    public String toString () {
+      return super.toString()+"[kind="+kind+", context="+context+", count="+count+"]";
+    }
+
+  } // class Event
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractWatchService.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractWatchService.java
new file mode 100644
index 0000000000..fded88eedb
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AbstractWatchService.java
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.ClosedWatchServiceException;
+import com.llamalab.safs.WatchEvent;
+import com.llamalab.safs.WatchKey;
+import com.llamalab.safs.WatchService;
+import com.llamalab.safs.Watchable;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.concurrent.LinkedBlockingDeque;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+public abstract class AbstractWatchService implements WatchService {
+
+  private final WatchKey CLOSE_KEY = new WatchKey() {
+
+    @Override
+    public Watchable watchable () {
+      return null;
+    }
+
+    @Override
+    public boolean isValid () {
+      return true;
+    }
+
+    @Override
+    public boolean reset () {
+      return true;
+    }
+
+    @Override
+    public void cancel () {
+    }
+
+    @Override
+    public List<WatchEvent<?>> pollEvents () {
+      return null;
+    }
+  };
+  private final LinkedBlockingDeque<WatchKey> pendingKeys = new LinkedBlockingDeque<WatchKey>();
+  private final AtomicBoolean closed = new AtomicBoolean();
+
+  final void offer (WatchKey key) {
+    pendingKeys.offer(key);
+  }
+
+  @Override
+  public final WatchKey poll () {
+    checkOpen();
+    return checkKey(pendingKeys.poll());
+  }
+
+  @Override
+  public final WatchKey poll (long timeout, TimeUnit unit) throws InterruptedException {
+    checkOpen();
+    return checkKey(pendingKeys.poll(timeout, unit));
+  }
+
+  @Override
+  public final WatchKey take () throws InterruptedException {
+    checkOpen();
+    return checkKey(pendingKeys.take());
+  }
+
+  @Override
+  public final void close () throws IOException {
+    if (closed.compareAndSet(false, true)) {
+      try {
+        implCloseService();
+      }
+      finally {
+        pendingKeys.clear();
+        pendingKeys.offer(CLOSE_KEY);
+      }
+    }
+  }
+
+  protected abstract void implCloseService () throws IOException;
+
+  public final boolean isOpen () {
+    return !closed.get();
+  }
+
+  private void checkOpen () {
+    if (closed.get())
+      throw new ClosedWatchServiceException();
+  }
+
+  private WatchKey checkKey (WatchKey key) {
+    if (CLOSE_KEY == key)
+      pendingKeys.offer(key);
+    checkOpen();
+    return key;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AttributeParser.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AttributeParser.java
new file mode 100644
index 0000000000..738cec2a8d
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/AttributeParser.java
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import java.util.EnumSet;
+import java.util.Iterator;
+
+final class AttributeParser<E extends Enum<E>> implements Iterable<E> {
+
+  private final Class<E> enumType;
+  private final String attributes;
+  private final String viewName;
+  private final boolean isDefault;
+
+  public AttributeParser (Class<E> enumType, String attributes, String viewName, boolean isDefault) {
+    this.enumType = enumType;
+    this.attributes = attributes;
+    this.viewName = viewName;
+    this.isDefault = isDefault;
+  }
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public Iterator<E> iterator () {
+    final int length = attributes.length();
+    int start = 0, index = 0;
+    boolean prefixed = false;
+    loop: while (index < length) {
+      switch (attributes.charAt(index)) {
+        case ':':
+          if (prefixed)
+            throw new IllegalArgumentException();
+          if (index != viewName.length() || !attributes.startsWith(viewName))
+            return Utils.emptyIterator();
+          start = ++index;
+          prefixed = true;
+          break;
+        case '*':
+          if (index != start || ++index != length)
+            throw new IllegalArgumentException();
+          if (!prefixed && !isDefault)
+            return Utils.emptyIterator();
+          return EnumSet.allOf(enumType).iterator();
+        case ',':
+          break loop;
+        default:
+          ++index;
+      }
+    }
+    if (!prefixed && !isDefault)
+      return Utils.emptyIterator();
+    return new CommaSeparatedIterator(start, index);
+  }
+
+  private final class CommaSeparatedIterator implements Iterator<E> {
+
+    private int start;
+    private int index;
+
+    public CommaSeparatedIterator (int start, int index) {
+      this.start = start;
+      this.index = index;
+    }
+
+    @Override
+    public boolean hasNext () {
+      return start < index;
+    }
+
+    @Override
+    public E next () {
+      final E element = Enum.valueOf(enumType, attributes.substring(start, index));
+      index = attributes.indexOf(',', start = index + 1);
+      if (index == -1)
+        index = attributes.length();
+      return element;
+    }
+
+    @Override
+    public void remove () {
+      throw new UnsupportedOperationException();
+    }
+
+  } // class CommaSeparatedIterator
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/BasicFileAttribute.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/BasicFileAttribute.java
new file mode 100644
index 0000000000..d5e416e4ec
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/BasicFileAttribute.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.attribute.BasicFileAttributes;
+import com.llamalab.safs.attribute.FileAttribute;
+
+public enum BasicFileAttribute {
+  fileKey {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.fileKey();
+    }
+  },
+  isDirectory {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.isDirectory();
+    }
+  },
+  isRegularFile {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.isRegularFile();
+    }
+  },
+  isSymbolicLink {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.isSymbolicLink();
+    }
+  },
+  isOther {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.isOther();
+    }
+  },
+  size {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.size();
+    }
+  },
+  creationTime {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.creationTime();
+    }
+  },
+  lastModifiedTime {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.lastModifiedTime();
+    }
+  },
+  lastAccessTime {
+    @Override
+    public Object valueOf (BasicFileAttributes attrs) {
+      return attrs.lastAccessTime();
+    }
+  };
+
+  public static final String VIEW_NAME = "basic";
+
+  public abstract Object valueOf (BasicFileAttributes attrs);
+
+  public FileAttribute newFileAttribute (Object value) {
+    return new BasicFileAttributeValue(this, value);
+  }
+
+  public static Iterable<BasicFileAttribute> parse (String attributes) {
+    return new AttributeParser<BasicFileAttribute>(BasicFileAttribute.class, attributes, VIEW_NAME, true);
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/BasicFileAttributeValue.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/BasicFileAttributeValue.java
new file mode 100644
index 0000000000..3c56b1542e
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/BasicFileAttributeValue.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.attribute.FileAttribute;
+
+public final class BasicFileAttributeValue implements FileAttribute<Object> {
+
+  private final BasicFileAttribute type;
+  private final Object value;
+
+  public BasicFileAttributeValue (BasicFileAttribute type, Object value) {
+    if (type == null || value == null)
+      throw new NullPointerException();
+    this.type = type;
+    this.value = value;
+  }
+
+  @Override
+  public String name () {
+    return BasicFileAttribute.VIEW_NAME + ":" + type;
+  }
+
+  @Override
+  public Object value () {
+    return value;
+  }
+
+  public BasicFileAttribute type () {
+    return type;
+  }
+
+  @Override
+  public int hashCode () {
+    return type.hashCode();
+  }
+
+  @Override
+  public boolean equals (Object other) {
+    return other instanceof BasicFileAttributeValue
+        && type == ((BasicFileAttributeValue)other).type;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/CompleteBasicFileAttributes.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/CompleteBasicFileAttributes.java
new file mode 100644
index 0000000000..d2f42a6f9a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/CompleteBasicFileAttributes.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.attribute.FileTime;
+
+public class CompleteBasicFileAttributes extends PartialBasicFileAttributes {
+
+  private final Object fileKey;
+  private final FileTime creationTime;
+  private final FileTime lastModifiedTime;
+  private final FileTime lastAccessTime;
+
+  public CompleteBasicFileAttributes (Object fileKey, FileType type, long size, FileTime creationTime, FileTime lastModifiedTime, FileTime lastAccessTime) {
+    super(type, size);
+    this.fileKey = fileKey;
+    this.creationTime = creationTime;
+    this.lastModifiedTime = lastModifiedTime;
+    this.lastAccessTime = lastAccessTime;
+  }
+
+  @Override
+  public final Object fileKey () {
+    return fileKey;
+  }
+
+  @Override
+  public final FileTime creationTime () {
+    return creationTime;
+  }
+
+  @Override
+  public final FileTime lastModifiedTime () {
+    return lastModifiedTime;
+  }
+
+  @Override
+  public final FileTime lastAccessTime () {
+    return lastAccessTime;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/DefaultFileSystem.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/DefaultFileSystem.java
new file mode 100644
index 0000000000..9f653647cc
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/DefaultFileSystem.java
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.Path;
+
+public interface DefaultFileSystem {
+  public Path getCacheDirectory ();
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/FileType.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/FileType.java
new file mode 100644
index 0000000000..24b7fe9f21
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/FileType.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+public enum FileType {
+  DIRECTORY,
+  REGULAR_FILE,
+  SYMBOLIC_LINK,
+  OTHER,
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/PartialBasicFileAttributes.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/PartialBasicFileAttributes.java
new file mode 100644
index 0000000000..2ba3240f35
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/PartialBasicFileAttributes.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.attribute.BasicFileAttributes;
+
+public abstract class PartialBasicFileAttributes implements BasicFileAttributes {
+
+  private final FileType type;
+  private final long size;
+
+  protected PartialBasicFileAttributes (FileType type, long size) {
+    this.type = type;
+    this.size = size;
+  }
+
+  @Override
+  public final boolean isDirectory () {
+    return FileType.DIRECTORY == type;
+  }
+
+  @Override
+  public final boolean isRegularFile () {
+    return FileType.REGULAR_FILE == type;
+  }
+
+  @Override
+  public final boolean isSymbolicLink () {
+    return FileType.SYMBOLIC_LINK == type;
+  }
+
+  @Override
+  public final boolean isOther () {
+    return FileType.OTHER == type;
+  }
+
+  @Override
+  public final long size () {
+    return size;
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/PathDescender.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/PathDescender.java
new file mode 100644
index 0000000000..c8a8ccdfd7
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/PathDescender.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import java.util.Iterator;
+
+public class PathDescender<T extends SegmentEntry> implements Iterator<PathDescender.Event> {
+
+  public enum Event {
+    DIRECTORY,
+    FILE,
+    MISSING_DIRECTORY,
+    MISSING_FILE
+  }
+
+  private final Iterator<String> segments;
+  private SegmentEntry parent;
+  private String segment;
+  private int index;
+
+  public PathDescender (T root, Iterator<String> segments) {
+    this.parent = root;
+    this.segments = segments;
+  }
+
+  @Override
+  public boolean hasNext () {
+    return index >= 0 && segments.hasNext();
+  }
+
+  @Override
+  public Event next () {
+    if (segment != null)
+      parent = parent.children[index];
+    if ((index = parent.binarySearch(segment = segments.next())) >= 0)
+      return segments.hasNext() ? Event.DIRECTORY : Event.FILE;
+    else
+      return segments.hasNext() ? Event.MISSING_DIRECTORY : Event.MISSING_FILE;
+  }
+
+  @Override
+  public void remove () {
+    parent.remove(index);
+    index = -1;
+  }
+
+  public void set (T entry) {
+    entry.segment = segment;
+    index = parent.put(index, entry);
+  }
+
+  public String segment () {
+    return segment;
+  }
+
+  @SuppressWarnings("unchecked")
+  public T parent () {
+    return (T)parent;
+  }
+
+  @SuppressWarnings("unchecked")
+  public T entry () {
+    return (T)parent.children[index];
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/SearchSet.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/SearchSet.java
new file mode 100644
index 0000000000..e88762a50f
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/SearchSet.java
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import java.util.AbstractSet;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+/**
+ * Values must MUST implement Comparable.
+ */
+public class SearchSet<T> extends AbstractSet<T> implements Comparator<Object> {
+
+  private final Object[] elements;
+
+  @SafeVarargs
+  public SearchSet (T... elements) {
+    this.elements = elements;
+    Arrays.sort(elements, this);
+  }
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public Iterator<T> iterator () {
+    return new Iterator<T>() {
+      private int index;
+
+      @Override
+      public boolean hasNext () {
+        return index < elements.length;
+      }
+
+      @SuppressWarnings("unchecked")
+      @Override
+      public T next () {
+        if (index >= elements.length)
+          throw new NoSuchElementException();
+        return (T)elements[index++];
+      }
+
+      @Override
+      public void remove () {
+        throw new UnsupportedOperationException();
+      }
+    };
+  }
+
+  @Override
+  public int size () {
+    return elements.length;
+  }
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public boolean addAll (Collection<? extends T> collection) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public void clear () {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public boolean contains (Object object) {
+    return Arrays.binarySearch(elements, object, this) >= 0;
+  }
+
+  @Override
+  public boolean remove (Object object) {
+    throw new UnsupportedOperationException();
+  }
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public boolean retainAll (Collection<?> collection) {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public boolean removeAll (Collection<?> collection) {
+    throw new UnsupportedOperationException();
+  }
+
+  @SuppressWarnings("unchecked")
+  @Override
+  public int compare (Object lhs, Object rhs) {
+    if (lhs == rhs)
+      return 0;
+    if (lhs == null)
+      return 1;
+    if (rhs == null)
+      return -1;
+    final Class lc = lhs.getClass();
+    final Class rc = rhs.getClass();
+    return (lc != rc) ? lc.getName().compareTo(rc.getName()) : ((Comparable)lhs).compareTo(rhs);
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/SegmentEntry.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/SegmentEntry.java
new file mode 100644
index 0000000000..56af7003cf
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/SegmentEntry.java
@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.unix.UnixPath;
+
+import java.lang.reflect.Array;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+public class SegmentEntry<T extends SegmentEntry<T>> implements Iterable<T> {
+
+  private static final SegmentEntry[] EMPTY = new SegmentEntry[0];
+
+  String segment;
+  SegmentEntry[] children = EMPTY;
+  int size;
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public Iterator<T> iterator () {
+    return new Iterator<T>() {
+
+      private int index;
+
+      @Override
+      public boolean hasNext () {
+        return index < size;
+      }
+
+      @SuppressWarnings("unchecked")
+      @Override
+      public T next () {
+        if (index >= size)
+          throw new NoSuchElementException();
+        return (T)children[index++];
+      }
+
+      @Override
+      public void remove () {
+        if (index == 0)
+          throw new IllegalStateException();
+        SegmentEntry.this.remove(--index);
+      }
+    };
+  }
+
+  public final boolean isEmpty () {
+    return size == 0;
+  }
+
+  public final void clear () {
+    size = 0;
+    Arrays.fill(children, null);
+  }
+
+  @SuppressWarnings({ "unchecked", "SuspiciousSystemArraycopy" })
+  public T[] toArray (T[] a) {
+    if (size > a.length)
+      a = (T[])Array.newInstance(a.getClass().getComponentType(), size);
+    System.arraycopy(children, 0, a, 0, size);
+    return a;
+  }
+
+  public T getDescendant (UnixPath path) {
+    return getDescendant(path.stringIterator());
+  }
+
+  @SuppressWarnings("unchecked")
+  public T getDescendant (Iterator<String> segments) {
+    SegmentEntry parent = this;
+    while (segments.hasNext()) {
+      final int index = parent.binarySearch(segments.next());
+      if (index < 0)
+        return null;
+      parent = parent.children[index];
+    }
+    return (T)parent;
+  }
+
+  public final PathDescender<T> descentor (UnixPath path) {
+    return descentor(path.stringIterator());
+  }
+
+  @SuppressWarnings("unchecked")
+  public final PathDescender<T> descentor (Iterator<String> segments) {
+    return new PathDescender<T>((T)this, segments);
+  }
+
+  final int binarySearch (String segment) {
+    final SegmentEntry[] c = children;
+    int low = 0;
+    int high = size - 1;
+    while (low <= high) {
+      final int mid = (low + high) >>> 1;
+      final int cmp = c[mid].segment.compareTo(segment);
+      if (cmp < 0)
+        low = mid + 1;
+      else if (cmp > 0)
+        high = mid - 1;
+      else
+        return mid; // key found
+    }
+    return -(low + 1); // key not found.
+  }
+
+  final int put (int index, SegmentEntry child) {
+    if (index < 0) {
+      index = ~index;
+      final SegmentEntry[] oc = children;
+      final int s = size++;
+      if (s == oc.length) {
+        final SegmentEntry[] nc = new SegmentEntry[1 << (32 - Integer.numberOfLeadingZeros(s))];
+        System.arraycopy(oc, 0, nc, 0, index);
+        System.arraycopy(oc, index, nc, index + 1, s - index);
+        children = nc;
+        nc[index] = child;
+      }
+      else {
+        System.arraycopy(oc, index, oc, index + 1, s - index);
+        oc[index] = child;
+      }
+    }
+    else
+      children[index] = child;
+    return index;
+  }
+
+  final void remove (int index) {
+    if (index < 0 || size <= index)
+      throw new IndexOutOfBoundsException();
+    System.arraycopy(children, index + 1, children, index, --size - index);
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/UserPrincipalFactory.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/UserPrincipalFactory.java
new file mode 100644
index 0000000000..ec21d519e3
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/UserPrincipalFactory.java
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.attribute.GroupPrincipal;
+import com.llamalab.safs.attribute.UserPrincipal;
+import com.llamalab.safs.attribute.UserPrincipalLookupService;
+
+import java.io.IOException;
+
+public class UserPrincipalFactory extends UserPrincipalLookupService {
+
+  @Override
+  public UserPrincipal lookupPrincipalByName (String name) throws IOException {
+    return new User(name);
+  }
+
+  @Override
+  public GroupPrincipal lookupPrincipalByGroupName (String group) throws IOException {
+    return new Group(group);
+  }
+
+  protected static class User implements UserPrincipal {
+
+    private final String name;
+
+    public User (String name) {
+      if (name == null)
+        throw new NullPointerException();
+      this.name = name;
+    }
+
+    @Override
+    public String getName () {
+      return name;
+    }
+
+    @Override
+    public String toString () {
+      return super.toString()+"[name="+name+"]";
+    }
+
+    @Override
+    public boolean equals (Object other) {
+      return other instanceof User && name.equals(((User)other).name);
+    }
+
+    @Override
+    public int hashCode () {
+      return name.hashCode();
+    }
+
+  }
+
+  protected static class Group extends User implements GroupPrincipal {
+
+    public Group (String name) {
+      super(name);
+    }
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/Utils.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/Utils.java
new file mode 100644
index 0000000000..1884e1f08d
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/Utils.java
@@ -0,0 +1,455 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.CopyOption;
+import com.llamalab.safs.DirectoryStream;
+import com.llamalab.safs.FileVisitOption;
+import com.llamalab.safs.FileVisitResult;
+import com.llamalab.safs.FileVisitor;
+import com.llamalab.safs.Files;
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.OpenOption;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.SimpleFileVisitor;
+import com.llamalab.safs.attribute.BasicFileAttributes;
+import com.llamalab.safs.attribute.FileTime;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+import java.nio.channels.FileChannel;
+import java.nio.channels.ReadableByteChannel;
+import java.nio.channels.WritableByteChannel;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Calendar;
+import java.util.GregorianCalendar;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Locale;
+import java.util.NoSuchElementException;
+import java.util.TimeZone;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
+
+@SuppressWarnings("unused")
+public final class Utils {
+
+  private static final int BUFFER_SIZE = 8192;
+
+  public static final Charset UTF_8 = Charset.forName("utf-8");
+  public static final Charset US_ASCII = Charset.forName("US-ASCII");
+
+  public static final TimeZone UTC = TimeZone.getTimeZone("UTC");
+  public static final FileTime ZERO_TIME = FileTime.fromMillis(0);
+
+  public static final String[] EMPTY_STRING_ARRAY = new String[0];
+  public static final CharSequence[] EMPTY_CHAR_SEQUENCE_ARRAY = new CharSequence[0];
+  public static final CopyOption[] EMPTY_COPY_OPTION_ARRAY = new CopyOption[0];
+  public static final LinkOption[] EMPTY_LINK_OPTION_ARRAY = new LinkOption[0];
+  public static final FileVisitOption[] EMPTY_FILE_VISIT_OPTION_ARRAY = new FileVisitOption[0];
+  public static final OpenOption[] EMPTY_OPEN_OPTION_ARRAY = new OpenOption[0];
+
+  public static final DirectoryStream.Filter<Path> ACCEPT_ALL_FILTER = new DirectoryStream.Filter<Path> () {
+    @Override
+    public boolean accept (Path entry) throws IOException {
+      return true;
+    }
+  };
+
+  public static final FileVisitor<Path> DELETE_FILE_VISITOR = new SimpleFileVisitor<Path>() {
+
+    @Override
+    public FileVisitResult postVisitDirectory (Path dir, IOException e) throws IOException {
+      if (e != null)
+        throw e;
+      Files.delete(dir);
+      return FileVisitResult.CONTINUE;
+    }
+
+    @Override
+    public FileVisitResult visitFile (Path file, BasicFileAttributes attrs) throws IOException {
+      Files.delete(file);
+      return FileVisitResult.CONTINUE;
+    }
+
+    @Override
+    public FileVisitResult visitFileFailed (Path file, IOException e) throws IOException {
+      return FileVisitResult.CONTINUE;
+    }
+
+  };
+
+  private static final Iterator<?> EMPTY_ITERATOR = new Iterator<Object> () {
+    @Override
+    public boolean hasNext () {
+      return false;
+    }
+    @Override
+    public Object next () {
+      return null;
+    }
+    @Override
+    public void remove () {
+      throw new UnsupportedOperationException();
+    }
+  };
+
+  private Utils () {}
+
+  public static boolean equals (Object a, Object b) {
+    return a != null ? a.equals(b) : b == null;
+  }
+
+  public static boolean contentEquals (CharSequence cs1, CharSequence cs2) {
+    int l = cs1.length();
+    if (l != cs2.length())
+      return false;
+    for (int i = 0; --l >= 0; ++i) {
+      if (cs1.charAt(i) != cs2.charAt(i))
+        return false;
+    }
+    return true;
+  }
+
+  public static boolean contentEqualsIgnoreCase (CharSequence cs1, CharSequence cs2) {
+    int l = cs1.length();
+    if (l != cs2.length())
+      return false;
+    for (int i = 0; --l >= 0; ++i) {
+      char c1 = cs1.charAt(i);
+      char c2 = cs2.charAt(i);
+      if (c1 != c2) {
+        c1 = Character.toUpperCase(c1);
+        c2 = Character.toUpperCase(c2);
+        if (c1 != c2) {
+          c1 = Character.toLowerCase(c1);
+          c2 = Character.toLowerCase(c2);
+          if (c1 != c2)
+            return false;
+        }
+      }
+    }
+    return true;
+  }
+
+  /**
+   * Available in Java 1.8
+   * @see java.lang.String#join(CharSequence, Iterable)
+   */
+  public static String join (CharSequence delimiter, Iterable<? extends CharSequence> elements) {
+    final StringBuilder sb = new StringBuilder();
+    CharSequence d = "";
+    for (final CharSequence element : elements) {
+      sb.append(d).append(element);
+      d = delimiter;
+    }
+    return sb.toString();
+  }
+
+  /**
+   * Available in Java 1.7 (Android 4.4)
+   * @see java.util.Collections#emptyIterator()
+   */
+  @SuppressWarnings("unchecked")
+  public static <E> Iterator<E> emptyIterator () {
+    return (Iterator<E>)EMPTY_ITERATOR;
+  }
+
+  public static <E> Iterator<E> singletonIterator (final E element) {
+    return new Iterator<E>() {
+      private boolean started;
+      @Override
+      public boolean hasNext () {
+        return !started;
+      }
+      @Override
+      public E next () {
+        if (started)
+          throw new NoSuchElementException();
+        started = true;
+        return element;
+      }
+      @Override
+      public void remove () {
+        throw new UnsupportedOperationException();
+      }
+    };
+  }
+
+  public static <T> DirectoryStream<T> singletonDirectoryStream (final T entry) {
+    return new AbstractDirectoryStream<T>() {
+      private boolean started;
+      @Override
+      protected T advance () throws IOException {
+        if (started)
+          return null;
+        started = true;
+        return entry;
+      }
+    };
+  }
+
+
+  public static <T> List<T> listOf (Iterator<T> i) {
+    final List<T> list = new ArrayList<T>();
+    while (i.hasNext())
+      list.add(i.next());
+    return list;
+  }
+
+  public static <T> List<T> listOf (Iterable<T> i) {
+    return listOf(i.iterator());
+  }
+
+
+  public static void closeQuietly (Closeable c) {
+    try {
+      c.close();
+    }
+    catch (Throwable t) {
+      // ignore
+    }
+  }
+
+  /*
+  public static void unmap (MappedByteBuffer buf) {
+    try {
+      final Object cleaner = buf.getClass().getMethod("cleaner").invoke(buf);
+      cleaner.getClass().getMethod("clean").invoke(cleaner);
+    }
+    catch (Throwable t) {
+      // ignore
+    }
+  }
+  */
+
+
+  public static long transfer (ReadableByteChannel in, WritableByteChannel out) throws IOException {
+    if (in instanceof FileChannel)
+      return transfer((FileChannel)in, out);
+    else
+      return transfer(in, out, ByteBuffer.allocate(BUFFER_SIZE));
+  }
+
+  public static long transfer (ReadableByteChannel in, WritableByteChannel out, ByteBuffer buf) throws IOException {
+    long written = 0;
+    while (in.read(buf) != -1) {
+      buf.flip();
+      while (buf.hasRemaining())
+        written += out.write(buf);
+      buf.clear();
+    }
+    return written;
+  }
+
+  public static long transfer (FileChannel in, WritableByteChannel out) throws IOException {
+    long remaining = in.size();
+    long written = 0;
+    long b;
+    while (remaining > 0) {
+      b = in.transferTo(written, remaining, out);
+      remaining -= b;
+      written   += b;
+    }
+    return written;
+  }
+
+  public static long transfer (InputStream in, OutputStream out) throws IOException {
+    return transfer(in, out, new byte[BUFFER_SIZE]);
+  }
+
+  public static long transfer (InputStream in, OutputStream out, byte[] buf) throws IOException {
+    long written = 0;
+    int b;
+    while ((b = in.read(buf)) != -1) {
+      out.write(buf, 0, b);
+      written += b;
+    }
+    return written;
+  }
+
+  public static byte[] readAllBytes (InputStream in, int capacity) throws IOException {
+    byte[] data = new byte[capacity];
+    int size = 0;
+    for (int b;;) {
+      while ((b = in.read(data, size, capacity - size)) > 0)
+        size += b;
+      if (b < 0 || (b = in.read()) < 0)
+        break;
+      if (capacity == Integer.MAX_VALUE)
+        throw new OutOfMemoryError("Array size exceeded");
+      capacity = (int)Math.min(Math.max(capacity * 2L, BUFFER_SIZE), Integer.MAX_VALUE);
+      data = Arrays.copyOf(data, capacity);
+      data[size++] = (byte)b;
+    }
+    return (size == data.length) ? data : Arrays.copyOf(data, size);
+  }
+
+
+  // http://stackoverflow.com/a/522281/445360
+  private static final Pattern RFC3339 = Pattern.compile("(\\d{4})-(\\d{2})-(\\d{2})T(\\d{2}):(\\d{2}):(\\d{2})(?:\\.(\\d+))?(?:Z|([+-]\\d{2}:\\d{2}))");
+  public static long parseRfc3339 (CharSequence text) {
+    final Matcher m = RFC3339.matcher(text);
+    if (!m.matches())
+      throw new IllegalArgumentException();
+    String g = m.group(8);
+    final GregorianCalendar gc = new GregorianCalendar(TimeZone.getTimeZone((g != null) ? g : "UTC"), Locale.US);
+    //noinspection MagicConstant
+    gc.set(
+        Integer.parseInt(m.group(1)), Integer.parseInt(m.group(2)) - 1, Integer.parseInt(m.group(3)),
+        Integer.parseInt(m.group(4)), Integer.parseInt(m.group(5)), Integer.parseInt(m.group(6)));
+    g = m.group(7);
+    gc.set(Calendar.MILLISECOND, (g != null) ? Integer.parseInt(g)%1000 : 0);
+    return gc.getTimeInMillis();
+  }
+
+  public static String formatRfc3339 (long millis) {
+    final GregorianCalendar gc = new GregorianCalendar(Utils.UTC, Locale.US);
+    gc.setTimeInMillis(millis);
+    //noinspection MagicConstant
+    return String.format(Locale.US, (gc.get(Calendar.MILLISECOND) != 0) ? "%1$tFT%1$tT.%1$tLZ" : "%1$tFT%1$tTZ", gc);
+  }
+
+  /*
+  public static String formatRfc3339 (long time) {
+    final GregorianCalendar gc = new GregorianCalendar(TimeZone.getTimeZone("UTC"), Locale.US);
+    gc.setTimeInMillis(time);
+    return String.format(Locale.US, "%04d-%02d-%02dT%02d:%02d:%02d.%dZ",
+        gc.get(Calendar.YEAR), gc.get(Calendar.MONTH) + 1, gc.get(Calendar.DAY_OF_MONTH),
+        gc.get(Calendar.HOUR_OF_DAY), gc.get(Calendar.MINUTE), gc.get(Calendar.SECOND), gc.get(Calendar.MILLISECOND));
+  }
+  */
+
+  public static FileTime parseFileTime (CharSequence text) {
+    return FileTime.fromMillis(parseRfc3339(text));
+  }
+
+  public static String getFileExtension (Path path) {
+    final Path fileName = path.getFileName();
+    if (fileName != null) {
+      final String name = fileName.toString();
+      final int i = name.lastIndexOf('.');
+      if (i > 0 && i < name.length() - 1)
+        return name.substring(i + 1).toLowerCase(Locale.US);
+    }
+    return null;
+  }
+
+
+  /** Must be sorted! */
+  private static final char[] REGEX_ESCAPEES = { '$', '(', ')', '*', '+', '.', '?', '[', '\\', ']', '^', '{', '|' };
+
+  /**
+   * Only works with unix path separator (/).
+   */
+  public static String globToRegex (String glob, int s, int e) {
+    final StringBuilder regex = new StringBuilder("^");
+    int g = -1;
+    char c;
+    while (s < e) {
+      switch (c = glob.charAt(s++)) {
+
+        case '?':
+          regex.append("[^/]");
+          break;
+
+        case '*':
+          if (s < e && '*' == glob.charAt(s)) {
+            regex.append(".*");
+            ++s;
+          }
+          else
+            regex.append("[^/]*");
+          break;
+
+        case '[':
+          regex.append("[[");
+          c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid class"));
+          if ('^' == c) {
+            regex.append("\\^");
+            c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid class"));
+          }
+          else {
+            if ('!' == c) {
+              regex.append('^');
+              c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid class"));
+            }
+            if ('-' == c) {
+              regex.append('-');
+              c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid class"));
+            }
+          }
+          int l = Integer.MAX_VALUE;
+          while (']' != c) {
+            if ('/' == c)
+              throw new PatternSyntaxException("Invalid class character: /", glob, s - 1);
+            regex.append(c);
+            if ('-' == c) {
+              c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid range"));
+              if (c < l)
+                throw new PatternSyntaxException("Invalid range", glob, s - 3);
+              l = Integer.MAX_VALUE;
+              continue;
+            }
+            else
+              l = c;
+            c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid range"));
+          }
+          regex.append("]&&[^/]]");
+          break;
+
+        case '{':
+          if (g != -1)
+            throw new PatternSyntaxException("Nested group", glob, s - 1);
+          regex.append("(?:");
+          g = s;
+          break;
+        case ',':
+          regex.append((g != -1) ? '|' : ',');
+          break;
+        case '}':
+          regex.append((g != -1) ? ')' : '}');
+          g = -1;
+          break;
+
+        case '\\':
+          c = glob.charAt(checkGlobEnd(glob, s++, e, "Invalid escape"));
+          // fall thu
+        default:
+          if (Arrays.binarySearch(REGEX_ESCAPEES, c) >= 0)
+            regex.append("\\");
+          regex.append(c);
+      }
+    }
+    if (g != -1)
+      throw new PatternSyntaxException("Invalid group", glob, g - 1);
+    return regex.append('$').toString();
+  }
+
+  private static int checkGlobEnd (String glob, int s, int e, String message) {
+    if (s == e)
+      throw new PatternSyntaxException(message, glob, s - 1);
+    return s;
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/WatchEventKind.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/WatchEventKind.java
new file mode 100644
index 0000000000..929b1cca44
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/internal/WatchEventKind.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.internal;
+
+import com.llamalab.safs.WatchEvent;
+
+public class WatchEventKind<T> implements WatchEvent.Kind<T> {
+
+  private final String name;
+  private final Class<T> type;
+
+  public WatchEventKind (String name, Class<T> type) {
+    this.name = name;
+    this.type = type;
+  }
+
+  @Override
+  public final String name () {
+    return name;
+  }
+
+  @Override
+  public final Class<T> type () {
+    return type;
+  }
+
+  @Override
+  public final String toString () {
+    return name;
+  }
+
+}
\ No newline at end of file
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/DefaultJavaFileSystemProvider.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/DefaultJavaFileSystemProvider.java
new file mode 100644
index 0000000000..7dfbc9d17e
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/DefaultJavaFileSystemProvider.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.java;
+
+import com.llamalab.safs.FileSystem;
+import com.llamalab.safs.FileSystemAlreadyExistsException;
+import com.llamalab.safs.Path;
+
+import java.io.IOException;
+import java.net.URI;
+import java.util.Map;
+
+public final class DefaultJavaFileSystemProvider extends JavaFileSystemProvider {
+
+  private final FileSystem fileSystem = new JavaFileSystem(this);
+
+  @Override
+  public FileSystem getFileSystem (URI uri) {
+    checkUri(uri);
+    return fileSystem;
+  }
+
+  @Override
+  public FileSystem newFileSystem (URI uri, Map<String,?> env) throws IOException {
+    checkUri(uri);
+    throw new FileSystemAlreadyExistsException();
+  }
+
+  @Override
+  public FileSystem newFileSystem (Path path, Map<String,?> env) throws IOException {
+    checkPath(path);
+    throw new FileSystemAlreadyExistsException();
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/JavaFileSystem.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/JavaFileSystem.java
new file mode 100644
index 0000000000..e7dc16f30f
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/JavaFileSystem.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.java;
+
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.NoSuchFileException;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.internal.DefaultFileSystem;
+import com.llamalab.safs.spi.FileSystemProvider;
+import com.llamalab.safs.unix.AbstractUnixFileSystem;
+
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * Only support {@link com.llamalab.safs.unix.UnixPath}.
+ */
+public class JavaFileSystem extends AbstractUnixFileSystem implements DefaultFileSystem {
+
+  protected volatile Path cacheDirectory;
+  protected volatile Path currentDirectory;
+
+  public JavaFileSystem (FileSystemProvider provider) {
+    super(provider);
+  }
+
+  @Override
+  public final void close () throws IOException {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public final boolean isOpen () {
+    return true;
+  }
+
+  @Override
+  public boolean isReadOnly () {
+    return false;
+  }
+
+  @Override
+  public Path getCacheDirectory () {
+    if (cacheDirectory == null)
+      cacheDirectory = getPathSanitized(System.getProperty("java.io.tmpdir"));
+    return cacheDirectory;
+  }
+
+  public final Path getCurrentDirectory () {
+    if (currentDirectory == null)
+      currentDirectory = getPathSanitized(System.getProperty("user.dir"));
+    return currentDirectory;
+  }
+
+  @Override
+  protected Path toRealPath (Path path, LinkOption... options) throws IOException {
+    final File file = path.toFile();
+    if (!file.exists())
+      throw new NoSuchFileException(path.toString());
+    for (final LinkOption option : options) {
+      if (LinkOption.NOFOLLOW_LINKS == option)
+        return path.toAbsolutePath().normalize();
+    }
+    return getPathSanitized(file.getCanonicalPath());
+  }
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/JavaFileSystemProvider.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/JavaFileSystemProvider.java
new file mode 100644
index 0000000000..6bfd11de76
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/JavaFileSystemProvider.java
@@ -0,0 +1,490 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.java;
+
+import com.llamalab.safs.AccessDeniedException;
+import com.llamalab.safs.AtomicMoveNotSupportedException;
+import com.llamalab.safs.CopyOption;
+import com.llamalab.safs.DirectoryNotEmptyException;
+import com.llamalab.safs.DirectoryStream;
+import com.llamalab.safs.FileAlreadyExistsException;
+import com.llamalab.safs.FileStore;
+import com.llamalab.safs.FileSystemException;
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.NoSuchFileException;
+import com.llamalab.safs.NotDirectoryException;
+import com.llamalab.safs.NotLinkException;
+import com.llamalab.safs.OpenOption;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.StandardCopyOption;
+import com.llamalab.safs.StandardOpenOption;
+import com.llamalab.safs.attribute.BasicFileAttributes;
+import com.llamalab.safs.attribute.FileAttribute;
+import com.llamalab.safs.attribute.FileTime;
+import com.llamalab.safs.channels.SeekableByteChannel;
+import com.llamalab.safs.internal.AbstractDirectoryStream;
+import com.llamalab.safs.internal.BasicFileAttributeValue;
+import com.llamalab.safs.internal.CompleteBasicFileAttributes;
+import com.llamalab.safs.internal.FileType;
+import com.llamalab.safs.internal.SearchSet;
+import com.llamalab.safs.internal.Utils;
+import com.llamalab.safs.spi.FileSystemProvider;
+import com.llamalab.safs.unix.AbstractUnixFileSystemProvider;
+import com.llamalab.safs.unix.UnixPath;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.FilenameFilter;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.RandomAccessFile;
+import java.nio.channels.FileChannel;
+import java.util.Set;
+
+/**
+ * Only support {@link UnixPath}.
+ */
+public abstract class JavaFileSystemProvider extends AbstractUnixFileSystemProvider {
+
+  public JavaFileSystemProvider () {}
+  public JavaFileSystemProvider (FileSystemProvider provider) {}
+
+  @Override
+  public String getScheme () {
+    return "file";
+  }
+
+  @Override
+  public FileStore getFileStore (Path path) throws IOException {
+    // TODO: possible?
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public boolean isSameFile (Path path1, Path path2) throws IOException {
+    if (path1.equals(path2))
+      return true;
+    return getPathType().isInstance(path1) && getPathType().isInstance(path2)
+        && path1.getFileSystem().equals(path2.getFileSystem())
+        && isSameFile(path1.toFile(), path2.toFile());
+  }
+
+  @Override
+  public boolean isHidden (Path path) throws IOException {
+    checkPath(path);
+    return ((UnixPath)path).isHidden();
+  }
+
+  @Override
+  public void createDirectory (Path dir, FileAttribute<?>... attrs) throws IOException {
+    checkPath(dir);
+    createDirectory(dir.toFile(), attrs);
+  }
+
+  @Override
+  public void delete (Path path) throws IOException {
+    checkPath(path);
+    delete(path.toFile(), false);
+  }
+
+  @Override
+  public void copy (Path source, Path target, CopyOption... options) throws IOException {
+    checkPath(source);
+    checkPath(target);
+    transfer(source, target, false, new SearchSet<CopyOption>(options));
+  }
+
+  @Override
+  public void move (Path source, Path target, CopyOption... options) throws IOException {
+    checkPath(source);
+    checkPath(target);
+    transfer(source, target, true, new SearchSet<CopyOption>(options));
+  }
+
+  // TODO: symbolic links
+  private void transfer (Path source, Path target, boolean move, Set<CopyOption> options) throws IOException {
+    final File sourceFile = source.toFile();
+    final BasicFileAttributes sourceAttrs = readBasicFileAttributes(sourceFile);
+    final File targetFile = target.toFile();
+    if (sourceFile.getCanonicalPath().equals(targetFile.getCanonicalPath()))
+      return;
+    // atomic
+    if (move && options.contains(StandardCopyOption.ATOMIC_MOVE)) {
+      if (sourceFile.renameTo(targetFile))
+        return;
+      throw new AtomicMoveNotSupportedException(source.toString(), target.toString(), "Rename failed");
+    }
+    // delete target
+    if (options.contains(StandardCopyOption.REPLACE_EXISTING))
+      delete(targetFile, true); // throws DirectoryNotEmptyException
+    else if (targetFile.exists())
+      throw new FileAlreadyExistsException(target.toString());
+    // rename
+    if (move && sourceFile.renameTo(targetFile))
+      return;
+    // transfer
+    if (sourceAttrs.isDirectory()) {
+      if (move && isNonEmptyDirectory(sourceFile))
+        throw new DirectoryNotEmptyException(source.toString());
+      createDirectory(target);
+    }
+    else
+      copyFile(sourceFile, targetFile);
+    try {
+      if (options.contains(StandardCopyOption.COPY_ATTRIBUTES))
+        setLastModifiedTime(targetFile, sourceAttrs.lastModifiedTime());
+      if (move)
+        delete(sourceFile, false);
+    }
+    catch (IOException e) {
+      //noinspection ResultOfMethodCallIgnored
+      targetFile.delete();
+      throw e;
+    }
+    catch (RuntimeException  e) {
+      //noinspection ResultOfMethodCallIgnored
+      targetFile.delete();
+      throw e;
+    }
+  }
+
+  @Override
+  public InputStream newInputStream (Path path, OpenOption... options) throws IOException {
+    checkPath(path);
+    return newInputStream(path.toFile(), (options.length == 0) ? DEFAULT_NEW_INPUT_STREAM_OPTIONS : new SearchSet<OpenOption>(options));
+  }
+
+  // TODO: LinkOption.NOFOLLOW_LINKS
+  private InputStream newInputStream (File file, Set<? extends OpenOption> options) throws IOException {
+    if (options.contains(StandardOpenOption.WRITE))
+      throw new IllegalArgumentException();
+    try {
+      return new FileInputStream(file);
+    }
+    catch (IOException e) {
+      throw toProperException(e, file.toString(), null);
+    }
+  }
+
+  @Override
+  public OutputStream newOutputStream (Path path, OpenOption... options) throws IOException {
+    checkPath(path);
+    return newOutputStream(path.toFile(), (options.length == 0) ? DEFAULT_NEW_OUTPUT_STREAM_OPTIONS : new SearchSet<OpenOption>(options));
+  }
+
+  // TODO: LinkOption.NOFOLLOW_LINKS
+  private OutputStream newOutputStream (File file, Set<? extends OpenOption> options) throws IOException {
+    if (!options.contains(StandardOpenOption.WRITE))
+      throw new IllegalArgumentException();
+    try {
+      checkCreateOptions(file, options);
+      return new FileOutputStream(file, options.contains(StandardOpenOption.APPEND));
+    }
+    catch (IOException e) {
+      throw toProperException(e, file.toString(), null);
+    }
+  }
+
+  @Override
+  public SeekableByteChannel newByteChannel (Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs) throws IOException {
+    checkPath(path);
+    return newByteChannel(path.toFile(), options, attrs);
+  }
+
+  // TODO: LinkOption.NOFOLLOW_LINKS
+  private SeekableByteChannel newByteChannel (File file, Set<? extends OpenOption> options, FileAttribute<?>... attrs) throws IOException {
+    try {
+      if (!options.contains(StandardOpenOption.WRITE))
+        return new SeekableByteChannelWrapper(new RandomAccessFile(file, "r").getChannel(), false);
+      checkCreateOptions(file, options);
+      final RandomAccessFile raf = new RandomAccessFile(file, toModeString(options));
+      if (options.contains(StandardOpenOption.TRUNCATE_EXISTING)) {
+        try {
+          raf.setLength(0);
+        }
+        catch (IOException e) {
+          Utils.closeQuietly(raf);
+          throw e;
+        }
+      }
+      return new SeekableByteChannelWrapper(raf.getChannel(), options.contains(StandardOpenOption.APPEND));
+    }
+    catch (IOException e) {
+      throw toProperException(e, file.toString(), null);
+    }
+  }
+
+  private static String toModeString (Set<? extends OpenOption> options) {
+    if (options.contains(StandardOpenOption.SYNC))
+      return "rws";
+    if (options.contains(StandardOpenOption.DSYNC))
+      return "rwd";
+    return "rw";
+  }
+
+  private static void checkCreateOptions (File file, Set<? extends OpenOption> options) throws IOException {
+    if (options.contains(StandardOpenOption.CREATE_NEW)) {
+      if (file.exists())
+        throw new FileAlreadyExistsException(file.toString());
+    }
+    else if (!options.contains(StandardOpenOption.CREATE)) {
+      if (!file.exists())
+        throw new NoSuchFileException(file.toString());
+    }
+  }
+
+  /*
+  private RandomAccessFile newRandomAccessFile (File file, Set<? extends OpenOption> options) throws IOException {
+    try {
+      if (!options.contains(StandardOpenOption.WRITE))
+        return new RandomAccessFile(file, toModeString(options));
+      final RandomAccessFile raf = new RandomAccessFile(file, toModeString(options));
+      if (options.contains(StandardOpenOption.TRUNCATE_EXISTING)) {
+        try {
+          raf.setLength(0);
+        }
+        catch (IOException e) {
+          Utils.closeQuietly(raf);
+          throw e;
+        }
+      }
+      return raf;
+    }
+    catch (IOException e) {
+      throw toProperException(e, file.toString(), null);
+    }
+  }
+  */
+
+  /*
+  @Override
+  public void createSymbolicLink (Path link, Path target) throws IOException {
+    checkPaths(link, target);
+    createSymbolicLink(link.toFile(), target.toFile());
+  }
+
+  protected void createSymbolicLink (File link, File target) throws IOException {
+    final Process process = Runtime.getRuntime().exec(new String[] { "ln", "-s", target.toString(), link.toString() });
+    try {
+      if (0 != process.waitFor()) {
+        if (target.exists())
+          throw new FileAlreadyExistsException(target.toString());
+        else
+          throw new IOException("ln command failure");
+      }
+    }
+    catch (InterruptedException e) {
+      throw (IOException)new InterruptedIOException().initCause(e);
+    }
+    finally {
+      process.destroy();
+    }
+  }
+  */
+
+  @Override
+  public Path readSymbolicLink (Path link) throws IOException {
+    final Path parent = link.getParent();
+    if (parent != null)
+      link = parent.toRealPath().resolve(link.getFileName());
+    final Path real = link.toRealPath();
+    if (real.equals(link.toAbsolutePath()))
+      throw new NotLinkException(link.toString());
+    return real;
+  }
+
+  /**
+   * May be overridden with a faster implementation.
+   */
+  protected boolean isSymbolicLink (Path path) {
+    return isSymbolicLink(path.toFile());
+  }
+
+  private boolean isSymbolicLink (File file) {
+    try {
+      final File parent = file.getParentFile();
+      if (parent != null)
+        file = new File(parent.getCanonicalPath(), file.getName());
+      return !file.getCanonicalPath().equals(file.getAbsolutePath());
+    }
+    catch (IOException e) {
+      return false;
+    }
+  }
+
+  @SuppressWarnings("unchecked")
+  @Override
+  public <A extends BasicFileAttributes> A readAttributes (Path path, Class<A> type, LinkOption... options) throws IOException {
+    checkPath(path);
+    if (BasicFileAttributes.class != type)
+      throw new UnsupportedOperationException("Unsupported type: "+type);
+    return (A)readBasicFileAttributes(path.toFile(), options);
+  }
+
+  protected BasicFileAttributes readBasicFileAttributes (File file, LinkOption... options) throws IOException {
+    for (final LinkOption option : options) {
+      if (LinkOption.NOFOLLOW_LINKS == option) {
+        if (!isSymbolicLink(file))
+          break;
+        return new CompleteBasicFileAttributes(null, FileType.SYMBOLIC_LINK, 0, Utils.ZERO_TIME, Utils.ZERO_TIME, Utils.ZERO_TIME);
+      }
+    }
+    if (!file.exists())
+      throw new NoSuchFileException(file.toString());
+    final FileType fileType;
+    if (file.isDirectory())
+      fileType = FileType.DIRECTORY;
+    else if (file.isFile())
+      fileType = FileType.REGULAR_FILE;
+    else
+      fileType = FileType.OTHER;
+    return new CompleteBasicFileAttributes(
+        null,
+        fileType,
+        file.length(),
+        Utils.ZERO_TIME,
+        FileTime.fromMillis(file.lastModified()),
+        Utils.ZERO_TIME);
+  }
+
+  @Override
+  protected void setAttributes (Path path, Set<? extends FileAttribute<?>> attrs, LinkOption... options) throws IOException {
+    checkPath(path);
+    for (final FileAttribute<?> attr : attrs) {
+      if (attr instanceof BasicFileAttributeValue) {
+        switch (((BasicFileAttributeValue)attr).type()) {
+          case lastModifiedTime:
+            setLastModifiedTime(path.toFile(), (FileTime)attr.value());
+            continue;
+        }
+      }
+      throw new UnsupportedOperationException("Attribute: "+attr.name());
+    }
+  }
+
+  protected void setLastModifiedTime (File file, FileTime value) throws IOException {
+    if (!file.setLastModified(value.toMillis()))
+      throw new FileSystemException(file.toString(), null, "Failed to set last modified time");
+  }
+
+  @Override
+  public DirectoryStream<Path> newDirectoryStream (final Path dir, final DirectoryStream.Filter<? super Path> filter) throws IOException {
+    checkPath(dir);
+    if (filter == null)
+      throw new NullPointerException("filter");
+    try {
+      final File dirFile = dir.toFile();
+      final String[] files = dirFile.list();
+      if (files == null) {
+        if (dirFile.exists() && !dirFile.canRead())
+          throw new AccessDeniedException(dir.toString());
+        throw new NotDirectoryException(dir.toString());
+      }
+      return new AbstractDirectoryStream<Path>() {
+        private int index;
+        @Override
+        protected Path advance () throws IOException {
+          while (index < files.length) {
+            final Path entry = dir.resolve(files[index++]);
+            if (filter.accept(entry))
+              return entry;
+          }
+          return null;
+        }
+      };
+    }
+    catch (IOException e) {
+      throw toProperException(e, dir.toString(), null);
+    }
+  }
+
+  protected final void createDirectory (File dir, FileAttribute<?>... attrs) throws IOException {
+    if (!dir.mkdir()) {
+      if (dir.exists()) {
+        if (!dir.canWrite())
+          throw new AccessDeniedException(dir.toString());
+        throw new FileAlreadyExistsException(dir.toString());
+      }
+      throw new FileSystemException(dir.toString(), null, "Failed to create directory");
+    }
+  }
+
+  protected final void delete (File file, boolean ifExists) throws IOException {
+    if (!file.delete()) {
+      if (isNonEmptyDirectory(file))
+        throw new DirectoryNotEmptyException(file.toString());
+      if (file.exists()) {
+        if (!file.canWrite())
+          throw new AccessDeniedException(file.toString());
+        throw new FileSystemException(file.toString(), null, "Failed to delete file");
+      }
+      else if (!ifExists)
+        throw new NoSuchFileException(file.toString());
+    }
+  }
+
+  protected final void copyFile (File source, File target) throws IOException {
+    final FileChannel in;
+    try {
+      in = new FileInputStream(source).getChannel();
+    }
+    catch (IOException e) {
+      throw toProperException(e, source.toString(), null);
+    }
+    try {
+      final FileChannel out;
+      try {
+        out = new FileOutputStream(target).getChannel();
+      }
+      catch (IOException e) {
+        throw toProperException(e, target.toString(), null);
+      }
+      try {
+        Utils.transfer(in, out);
+      }
+      catch (IOException e) {
+        throw toProperException(e, source.toString(), target.toString());
+      }
+      finally {
+        out.close();
+      }
+    }
+    finally {
+      in.close();
+    }
+  }
+
+  protected final boolean isSameFile (File file1, File file2) throws IOException {
+    return file1.getCanonicalPath().equals(file2.getCanonicalPath());
+  }
+
+  protected final boolean isNonEmptyDirectory (File dir) {
+    final String[] names = dir.list(new FilenameFilter() {
+      private boolean found;
+      @Override
+      public boolean accept (File dir, String filename) {
+        if (found)
+          return false;
+        return found = true;
+      }
+    });
+    return names != null && names.length != 0;
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/SeekableByteChannelWrapper.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/SeekableByteChannelWrapper.java
new file mode 100644
index 0000000000..23c2e88f4a
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/java/SeekableByteChannelWrapper.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.java;
+
+import com.llamalab.safs.channels.SeekableByteChannel;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.FileChannel;
+
+final class SeekableByteChannelWrapper implements SeekableByteChannel {
+
+  private final FileChannel fc;
+  private final boolean append;
+
+  public SeekableByteChannelWrapper (FileChannel fc, boolean append) {
+    this.fc = fc;
+    this.append = append;
+  }
+
+  @Override
+  public void close () throws IOException {
+    fc.close();
+  }
+
+  @Override
+  public boolean isOpen () {
+    return fc.isOpen();
+  }
+
+  @Override
+  public int read (ByteBuffer dst) throws IOException {
+    return fc.read(dst);
+  }
+
+  @Override
+  public int write (ByteBuffer src) throws IOException {
+    if (append)
+      fc.position(fc.size());
+    return fc.write(src);
+  }
+
+  @Override
+  public long position () throws IOException {
+    return fc.position();
+  }
+
+  @Override
+  public SeekableByteChannel position (long newPosition) throws IOException {
+    fc.position(newPosition);
+    return this;
+  }
+
+  @Override
+  public long size () throws IOException {
+    return fc.size();
+  }
+
+  @Override
+  public SeekableByteChannel truncate (long size) throws IOException {
+    fc.truncate(size);
+    return this;
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/kotlin/io/path/PathUtils.kt b/mirai-console/backend/mirai-console/src/com/llamalab/safs/kotlin/io/path/PathUtils.kt
new file mode 100644
index 0000000000..b4a0c6256b
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/kotlin/io/path/PathUtils.kt
@@ -0,0 +1,28 @@
+package com.llamalab.safs.kotlin.io.path
+import com.llamalab.safs.LinkOption
+import com.llamalab.safs.Path
+import com.llamalab.safs.Files
+import com.llamalab.safs.OpenOption
+import com.llamalab.safs.attribute.FileAttribute
+import java.nio.charset.Charset
+
+public inline fun Path.isRegularFile(vararg options: LinkOption): Boolean = Files.isRegularFile(this, *options)
+public inline fun Path.readBytes(): ByteArray {
+    return Files.readAllBytes(this)
+}
+public inline fun Path.writeBytes(array: ByteArray, vararg options: OpenOption): Unit {
+    Files.write(this, array, *options)
+}
+public inline fun Path.createDirectories(vararg attributes: FileAttribute<*>): Path =
+    Files.createDirectories(this, *attributes)
+
+public fun createTempDirectory(directory: Path?, prefix: String? = null, vararg attributes: FileAttribute<*>): Path =
+    if (directory != null)
+        Files.createTempDirectory(directory, prefix, *attributes)
+    else
+        Files.createTempDirectory(prefix, *attributes)
+public inline fun createTempDirectory(prefix: String? = null, vararg attributes: FileAttribute<*>): Path = Files.createTempDirectory(prefix, *attributes)
+
+public fun Path.writeText(text: CharSequence, charset: Charset = Charsets.UTF_8, vararg options: OpenOption) {
+    Files.newOutputStream(this, *options).writer(charset).use { it.append(text) }
+}
\ No newline at end of file
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/spi/FileSystemProvider.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/spi/FileSystemProvider.java
new file mode 100644
index 0000000000..8596f6f892
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/spi/FileSystemProvider.java
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.spi;
+
+import com.llamalab.safs.CopyOption;
+import com.llamalab.safs.DirectoryStream;
+import com.llamalab.safs.FileStore;
+import com.llamalab.safs.FileSystem;
+import com.llamalab.safs.FileSystems;
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.NoSuchFileException;
+import com.llamalab.safs.OpenOption;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.attribute.BasicFileAttributes;
+import com.llamalab.safs.attribute.FileAttribute;
+import com.llamalab.safs.attribute.FileAttributeView;
+import com.llamalab.safs.channels.SeekableByteChannel;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.ServiceLoader;
+import java.util.Set;
+
+public abstract class FileSystemProvider {
+
+  protected FileSystemProvider () {}
+
+  public static List<FileSystemProvider> installedProviders () {
+    return InstalledFileSystemProvidersHolder.providers;
+  }
+
+  public abstract String getScheme ();
+  public abstract Path getPath (URI uri);
+  public abstract FileSystem getFileSystem (URI uri);
+  public abstract FileSystem newFileSystem (Path path, Map<String,?> env) throws IOException;
+  public abstract FileSystem newFileSystem (URI uri, Map<String,?> env) throws IOException;
+  public abstract FileStore getFileStore (Path path) throws IOException;
+  public abstract boolean isSameFile (Path path1, Path path2) throws IOException;
+  public abstract boolean isHidden (Path path) throws IOException;
+  public abstract void createDirectory (Path dir, FileAttribute<?>... attrs) throws IOException;
+  public abstract void delete (Path path) throws IOException;
+  public boolean deleteIfExists (Path path) throws IOException {
+    try {
+      delete(path);
+      return true;
+    }
+    catch (NoSuchFileException e) {
+      return false;
+    }
+  }
+  public abstract void copy (Path source, Path target, CopyOption... options) throws IOException;
+  public abstract void move (Path source,Path target, CopyOption... options) throws IOException;
+  public abstract InputStream newInputStream (Path path, OpenOption... options) throws IOException;
+  public abstract OutputStream newOutputStream (Path path, OpenOption... options) throws IOException;
+  public abstract SeekableByteChannel newByteChannel (Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs) throws IOException;
+  /*
+  public void createSymbolicLink (Path link, Path target) throws IOException {
+    throw new UnsupportedOperationException();
+  }
+  */
+  public Path readSymbolicLink (Path link) throws IOException {
+    throw new UnsupportedOperationException();
+  }
+  public abstract <A extends BasicFileAttributes> A readAttributes (Path path, Class<A> type, LinkOption... options) throws IOException;
+  public abstract Map<String,Object> readAttributes (Path path, String attributes, LinkOption... options) throws IOException;
+  public abstract void setAttribute (Path path, String attribute, Object value, LinkOption... options) throws IOException;
+  public abstract <V extends FileAttributeView> V getFileAttributeView (Path path, Class<V> type, LinkOption... options);
+
+  public abstract DirectoryStream<Path> newDirectoryStream (Path dir, DirectoryStream.Filter<? super Path> filter) throws IOException;
+
+  private static final class InstalledFileSystemProvidersHolder {
+
+    static final List<FileSystemProvider> providers = loadInstalledProviders();
+
+    private static List<FileSystemProvider> loadInstalledProviders () {
+      final List<FileSystemProvider> providers = new ArrayList<FileSystemProvider>();
+      providers.add(FileSystems.getDefault().provider());
+      for (final FileSystemProvider provider : ServiceLoader.load(FileSystemProvider.class, FileSystemProvider.class.getClassLoader())) {
+        if (!"file".equalsIgnoreCase(provider.getScheme()))
+          providers.add(provider);
+      }
+      return Collections.unmodifiableList(providers);
+    }
+
+  } // class InstalledFileSystemProvidersHolder
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/spi/FileTypeDetector.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/spi/FileTypeDetector.java
new file mode 100644
index 0000000000..e641cd6c33
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/spi/FileTypeDetector.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.spi;
+
+import com.llamalab.safs.Path;
+
+import java.io.IOException;
+
+/**
+ * System.setProperty("content.types.user.table", "/path/to/property/file"​);
+ */
+public abstract class FileTypeDetector {
+
+  protected FileTypeDetector () {}
+
+  public abstract String probeContentType (Path path) throws IOException;
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/AbstractUnixFileSystem.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/AbstractUnixFileSystem.java
new file mode 100644
index 0000000000..5b2ee0c278
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/AbstractUnixFileSystem.java
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.unix;
+
+import com.llamalab.safs.FileStore;
+import com.llamalab.safs.FileSystem;
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.PathMatcher;
+import com.llamalab.safs.WatchService;
+import com.llamalab.safs.attribute.UserPrincipalLookupService;
+import com.llamalab.safs.internal.BasicFileAttribute;
+import com.llamalab.safs.internal.Utils;
+import com.llamalab.safs.spi.FileSystemProvider;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Set;
+import java.util.regex.Pattern;
+
+public abstract class AbstractUnixFileSystem extends FileSystem {
+
+  protected final FileSystemProvider provider;
+  private volatile Path emptyDirectory;
+  private volatile Path rootDirectory;
+
+  public AbstractUnixFileSystem (FileSystemProvider provider) {
+    this.provider = provider;
+  }
+
+  @Override
+  public final FileSystemProvider provider () {
+    return provider;
+  }
+
+  @Override
+  public final Path getPath (String first, String... more) {
+    return getPathSanitized(UnixPath.sanitize(first, more));
+  }
+
+  public final Path getPath (String first) {
+    return getPathSanitized(UnixPath.sanitize(first, Utils.EMPTY_STRING_ARRAY));
+  }
+
+  protected Path getPathSanitized (String path) {
+    return new UnixPath(this, path);
+  }
+
+  @Override
+  public PathMatcher getPathMatcher (String syntaxAndPattern) {
+    final Pattern pattern;
+    if (syntaxAndPattern.startsWith("regex:"))
+      pattern = Pattern.compile(syntaxAndPattern.substring(6));
+    else if (syntaxAndPattern.startsWith("glob:"))
+      pattern = Pattern.compile(Utils.globToRegex(syntaxAndPattern, 5, syntaxAndPattern.length()));
+    else
+      throw new UnsupportedOperationException(syntaxAndPattern);
+    return new PathMatcher() {
+      @Override
+      public boolean matches (Path path) {
+        return pattern.matcher(path.toString()).matches();
+      }
+    };
+  }
+
+  protected abstract Path toRealPath (Path path, LinkOption... options) throws IOException;
+
+  @Override
+  public final String getSeparator() {
+    return "/";
+  }
+
+  @Override
+  public Set<String> supportedFileAttributeViews() {
+    return Collections.singleton(BasicFileAttribute.VIEW_NAME);
+  }
+
+  @Override
+  public Iterable<FileStore> getFileStores () {
+    return Collections.emptySet();
+  }
+
+  @Override
+  public final Iterable<Path> getRootDirectories () {
+    return Collections.singleton(getRootDirectory());
+  }
+
+  @Override
+  public UserPrincipalLookupService getUserPrincipalLookupService () {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public WatchService newWatchService () throws IOException {
+    throw new UnsupportedOperationException();
+  }
+
+  public abstract Path getCurrentDirectory ();
+
+  public final Path getEmptyDirectory () {
+    if (emptyDirectory == null)
+      emptyDirectory = getPathSanitized("");
+    return emptyDirectory;
+  }
+
+  public final Path getRootDirectory () {
+    if (rootDirectory == null)
+      rootDirectory = getPathSanitized("/");
+    return rootDirectory;
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/AbstractUnixFileSystemProvider.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/AbstractUnixFileSystemProvider.java
new file mode 100644
index 0000000000..d1918b3838
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/AbstractUnixFileSystemProvider.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.unix;
+
+import com.llamalab.safs.Path;
+import com.llamalab.safs.internal.AbstractFileSystemProvider;
+import com.llamalab.safs.internal.Utils;
+
+import java.net.URI;
+
+public abstract class AbstractUnixFileSystemProvider extends AbstractFileSystemProvider {
+
+  @Override
+  protected Class<? extends UnixPath> getPathType () {
+    return UnixPath.class;
+  }
+
+  @Override
+  public Path getPath (URI uri) {
+    if (!uri.isAbsolute() || uri.isOpaque() || uri.getAuthority() != null || uri.getFragment() != null || uri.getQuery() != null)
+      throw new IllegalArgumentException();
+    return new UnixPath((AbstractUnixFileSystem)getFileSystem(uri), UnixPath.sanitize(uri.getPath(), Utils.EMPTY_STRING_ARRAY));
+  }
+
+}
diff --git a/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/UnixPath.java b/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/UnixPath.java
new file mode 100644
index 0000000000..3f5674a1a7
--- /dev/null
+++ b/mirai-console/backend/mirai-console/src/com/llamalab/safs/unix/UnixPath.java
@@ -0,0 +1,551 @@
+/*
+ * Copyright (C) 2019 Henrik Lindqvist
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.llamalab.safs.unix;
+
+import com.llamalab.safs.LinkOption;
+import com.llamalab.safs.Path;
+import com.llamalab.safs.ProviderMismatchException;
+import com.llamalab.safs.WatchEvent;
+import com.llamalab.safs.WatchKey;
+import com.llamalab.safs.WatchService;
+import com.llamalab.safs.internal.Utils;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.URI;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+public class UnixPath implements Path {
+
+  private final AbstractUnixFileSystem fs;
+  private final String path;
+  private volatile short[] nameOffsets; // lazy
+
+  protected UnixPath (AbstractUnixFileSystem fs, String path) {
+    this.fs = fs;
+    this.path = path;
+  }
+
+  protected UnixPath (UnixPath other) {
+    this(other.fs, other.path);
+    this.nameOffsets = other.nameOffsets;
+  }
+
+  @Override
+  public final AbstractUnixFileSystem getFileSystem () {
+    return fs;
+  }
+
+  @Override
+  public final String toString () {
+    return path;
+  }
+
+  @Override
+  public final int hashCode () {
+    int hc = 17;
+    hc = 37*hc + fs.hashCode();
+    hc = 37*hc + path.hashCode();
+    return hc;
+  }
+
+  @Override
+  public boolean equals (Object obj) {
+    if (this == obj)
+      return true;
+    if (!(obj instanceof UnixPath))
+      return false;
+    final UnixPath other = (UnixPath)obj;
+    return fs.equals(other.fs)
+        && path.equals(other.path);
+  }
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public int compareTo (Path other) {
+    return path.compareTo(other.toString());
+  }
+
+  @Override
+  public final boolean isAbsolute () {
+    return path.startsWith("/");
+  }
+
+  public final boolean isHidden () {
+    return path.startsWith(".");
+  }
+
+  public final boolean isEmpty () {
+    return path.isEmpty();
+  }
+
+  public final boolean isRoot () {
+    return path.equals("/");
+  }
+
+  /**
+   * @return true if . or ..
+   */
+  public final boolean isDots () {
+    return ".".equals(path) || "..".equals(path);
+  }
+
+  private static final short[] ZERO_NAME_OFFSETS = new short[] { 0 };
+  private static final short[] EMPTY_NAME_OFFSETS = new short[0];
+
+  private short[] getNameOffsets () {
+    if (nameOffsets != null)
+      return nameOffsets;
+    final String path = this.path;
+    final int length = path.length();
+    if (length == 0)
+      return nameOffsets = ZERO_NAME_OFFSETS;
+    int count = 0;
+    int index = 0;
+    while (index < length) {
+      if ('/' != path.charAt(index)) {
+        if (index++ > 0xFFFF)
+          throw new ArrayStoreException();
+        ++count;
+        while (index < length && '/' != path.charAt(index))
+          ++index;
+      }
+      else
+        ++index;
+    }
+    if (count == 0)
+      return nameOffsets = EMPTY_NAME_OFFSETS;
+    final short[] offsets = new short[count];
+    index = 0;
+    count = 0;
+    while (index < length) {
+      if ('/' != path.charAt(index)) {
+        offsets[count++] = (short)index++;
+        while (index < length && '/' != path.charAt(index))
+          ++index;
+      }
+      else
+        ++index;
+    }
+    return nameOffsets = offsets;
+  }
+
+  @Override
+  public Path getRoot () {
+    return isAbsolute() ? fs.getRootDirectory() : null;
+  }
+
+  @Override
+  public Path getParent () {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (count == 0)
+      return null;
+    final int end = (offsets[count - 1] & 0xFFFF) - 1;
+    if (end <= 0)
+      return getRoot();
+    return fs.getPathSanitized(path.substring(0, end));
+  }
+
+  /*
+  public final Path getAncestor (int endIndex) {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (endIndex < 0 || count < endIndex)
+      throw new IllegalArgumentException();
+    if (count == 0)
+      return null;
+    if (endIndex == count)
+      return this;
+    final int end = (offsets[endIndex] & 0xFFFF) - 1;
+    if (end <= 0)
+      return getRoot();
+    return fs.getPathSanitized(path.substring(0, end));
+  }
+  */
+
+  @Override
+  public Path getFileName () {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (count == 0)
+      return null;
+    if (count == 1 && path.length() != 0 && '/' != path.charAt(0))
+      return this;
+    return fs.getPathSanitized(path.substring(offsets[count - 1] & 0xFFFF));
+  }
+
+  public final int getNameCount () {
+    return getNameOffsets().length;
+  }
+
+  public Path getName (int index) {
+    return subpath(index, index + 1);
+  }
+
+  public Path subpath (int beginIndex, int endIndex) {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (beginIndex < 0 || count < endIndex || endIndex <= beginIndex)
+      throw new IllegalArgumentException();
+    if (endIndex < count)
+      return fs.getPathSanitized(path.substring(offsets[beginIndex] & 0xFFFF, (offsets[endIndex] & 0xFFFF) - 1));
+    else
+      return fs.getPathSanitized(path.substring(offsets[beginIndex] & 0xFFFF));
+  }
+
+  @Override
+  public final boolean startsWith (Path other) {
+    return fs.equals(other.getFileSystem())
+        && startsWithSanitized(((UnixPath)other).path);
+  }
+
+  @Override
+  public final boolean startsWith (String other) {
+    return startsWithSanitized(sanitize(other, Utils.EMPTY_STRING_ARRAY));
+  }
+
+  private boolean startsWithSanitized (String other) {
+    if (!path.startsWith(other))
+      return false;
+    final int end = other.length();
+    return end == path.length() || '/' == path.charAt(end) || "/".equals(other);
+  }
+
+  public final boolean endsWith (Path other) {
+    return fs.equals(other.getFileSystem())
+        && endsWithSanitized(((UnixPath)other).path);
+  }
+
+  public final boolean endsWith (String other) {
+    return endsWithSanitized(sanitize(other, Utils.EMPTY_STRING_ARRAY));
+  }
+
+  private boolean endsWithSanitized (String other) {
+    if (!path.endsWith(other))
+      return false;
+    final int start = path.length() - other.length();
+    return start == 0 || '/' == path.charAt(start - 1);
+  }
+
+  @SuppressWarnings("NullableProblems")
+  @Override
+  public Iterator<Path> iterator () {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (count == 0)
+      return Utils.emptyIterator();
+    return new NameIterator<Path>(path, offsets, count) {
+      @Override
+      protected Path next (String path, int start, int end) {
+        return fs.getPathSanitized(path.substring(start, end));
+      }
+    };
+  }
+
+  public final Iterator<CharSequence> charSequenceIterator () {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (count == 0)
+      return Utils.emptyIterator();
+    return new NameIterator<CharSequence>(path, offsets, count) {
+      @Override
+      protected CharSequence next (String path, int start, int end) {
+        return path.subSequence(start, end);
+      }
+    };
+  }
+
+  public final Iterator<String> stringIterator () {
+    final short[] offsets = getNameOffsets();
+    final int count = offsets.length;
+    if (count == 0)
+      return Utils.emptyIterator();
+    return new NameIterator<String>(path, offsets, count) {
+      @Override
+      protected String next (String path, int start, int end) {
+        return path.substring(start, end);
+      }
+    };
+  }
+
+  // FIXME: horrid
+  @Override
+  public Path normalize () {
+    CharSequence[] names = Utils.EMPTY_CHAR_SEQUENCE_ARRAY;
+    int end = 0;
+    for (Iterator<CharSequence> i = charSequenceIterator(); i.hasNext();) {
+      final CharSequence n = i.next();
+      if ("..".contentEquals(n) && end > 0)
+        --end;
+      else if (!".".contentEquals(n)){
+        if (names.length == end)
+          names = Arrays.copyOf(names, Math.max(end*2, 8));
+        names[end++] = n;
+      }
+    }
+    if (end == 0)
+      return isAbsolute() ? fs.getRootDirectory() : fs.getEmptyDirectory();
+    return fs.getPath(join(names, 0, end, isAbsolute() ? "/" : ""));
+  }
+
+  // FIXME: horrid
+  @Override
+  public Path relativize (Path other) {
+    checkPath(other);
+    if (isAbsolute() != other.isAbsolute())
+      throw new IllegalArgumentException("Absolute vs relative");
+    //if (equals(that))
+    //  return fs.getEmptyDirectory();
+    final Iterator<CharSequence> bi = charSequenceIterator();
+    final Iterator<CharSequence> ci = ((UnixPath)other).charSequenceIterator();
+    final RelativizeHelper h = new RelativizeHelper();
+    CharSequence bn, cn = null;
+    out: while (bi.hasNext() && ci.hasNext()) {
+      while (".".contentEquals(bn = bi.next()))
+        if (!bi.hasNext()) break out;
+      while (".".contentEquals(cn = ci.next()))
+        if (!ci.hasNext()) break out;
+      if (!Utils.contentEquals(bn, cn)) {
+        h.base(bn);
+        break;
+      }
+      h.add(bn);
+      ++h.start;
+      cn = null;
+    }
+    while (bi.hasNext())
+      if (!".".contentEquals(bn = bi.next())) h.base(bn);
+    if (cn != null && !".".contentEquals(cn))
+      h.child(cn);
+    while (ci.hasNext())
+      if (!".".contentEquals(cn = ci.next())) h.child(cn);
+    return fs.getPathSanitized(join(h.names, h.start, h.end, ""));
+  }
+
+  private static final class RelativizeHelper {
+    public CharSequence[] names = new CharSequence[8];
+    public int start = 0, end = 0;
+    public void base (CharSequence value) {
+      if ("..".contentEquals(value) && start > 0)
+        --start;
+      else
+        add("..");
+    }
+    public void child (CharSequence value) {
+      if ("..".contentEquals(value) && start < end && !"..".contentEquals(names[end - 1]))
+        --end;
+      else
+        add(value);
+    }
+    public void add (CharSequence value) {
+      if (names.length == end)
+        names = Arrays.copyOf(names, end*2);
+      names[end++] = value;
+    }
+  } // class RelativizeHelper
+
+  @Override
+  public Path resolve (Path other) {
+    checkPath(other);
+    if (other.isAbsolute())
+      return other;
+    if (((UnixPath)other).isEmpty())
+      return this;
+    return fs.getPath(path, ((UnixPath)other).path);
+  }
+
+  @Override
+  public Path resolve (String other) {
+    if (other.startsWith("/"))
+      return fs.getPath(other);
+    if (other.isEmpty())
+      return this;
+    return fs.getPath(path, other);
+  }
+
+  public Path resolveSibling (Path other) {
+    checkPath(other);
+    final Path parent = getParent();
+    return (parent != null) ? parent.resolve(other) : other;
+  }
+
+  public Path resolveSibling (String other) {
+    final Path parent = getParent();
+    return (parent != null) ? parent.resolve(other) : fs.getPath(other);
+  }
+
+  @Override
+  public Path toAbsolutePath () {
+    return isAbsolute() ? this : fs.getCurrentDirectory().resolve(this);
+  }
+
+  @Override
+  public Path toRealPath (LinkOption... options) throws IOException {
+    return fs.toRealPath(this, options);
+  }
+
+  @Override
+  public File toFile () {
+    return new File(path);
+  }
+
+  @Override
+  public URI toUri () {
+    try {
+      return new URI(fs.provider().getScheme(), toAbsolutePath().toString(), null);
+    }
+    catch (Throwable t) {
+      throw new IllegalStateException(t); // shouldn't happen
+    }
+  }
+
+  private static final WatchEvent.Modifier[] EMPTY_MODIFIER_ARRAY = new WatchEvent.Modifier[0];
+
+  @Override
+  public final WatchKey register (WatchService service, WatchEvent.Kind<?>... kinds) throws IOException {
+    return register(service, kinds, EMPTY_MODIFIER_ARRAY);
+  }
+
+  @Override
+  public WatchKey register (WatchService service, WatchEvent.Kind<?>[] kinds, WatchEvent.Modifier... modifiers) throws IOException {
+    throw new UnsupportedOperationException();
+  }
+
+  private static void checkPath (Path path) {
+    if (!(path instanceof UnixPath))
+      throw (path == null) ? new NullPointerException() : new ProviderMismatchException();
+  }
+
+  /*
+  private static String sanitize (String path) {
+    return sanitize(path, Utils.EMPTY_STRING_ARRAY);
+  }
+  */
+
+  /**
+   * Removes double and tail slash
+   */
+  static String sanitize (String first, String[] more) {
+    CharSequence parent = "";
+    for (int i = -1, count = more.length;;) {
+      parent = sanitizeChunk(parent, first);
+      if (++i == count)
+        break;
+      first = more[i];
+    }
+    return parent.toString();
+  }
+
+  private static CharSequence sanitizeChunk (CharSequence parent, String path) {
+    int end = path.length();
+    if (end == 0)
+      return parent; // empty
+    while (end > 0 && '/' == path.charAt(end - 1)) --end;
+    if (end == 0)
+      return (parent.length() == 0) ? "/" : parent; // root
+    // At this point it's neither empty nor root.
+    int start = 0;
+    while (start < end && '/' == path.charAt(start)) ++start;
+    final int parentLength = parent.length();
+    int index = path.indexOf("//", start + 1);
+    if (index == -1 || index >= end) {
+      // no //
+      if (parentLength == 0) {
+        if (start > 0)
+          --start; // keep initial /
+        return path.substring(start, end);
+      }
+      if (parentLength == 1 && '/' == parent.charAt(0)) {
+        // root parent
+        if (start > 0)
+          return path.substring(start - 1, end);
+        else
+          return new StringBuilder("/").append(path, start, end);
+      }
+      final StringBuilder sb = (parent instanceof StringBuilder) ? (StringBuilder)parent : new StringBuilder(parent);
+      return sb.append('/').append(path, start, end);
+    }
+    // found //
+    final StringBuilder sb = (parent instanceof StringBuilder) ? (StringBuilder)parent : new StringBuilder(parent);
+    if (parentLength == 0) {
+      if (start > 0)
+        --start; // keep initial /
+    }
+    else if (parentLength != 1 || '/' != parent.charAt(0)) {
+      // not root parent
+      sb.append('/');
+    }
+    while (++index < end) {
+      sb.append(path, start, index);
+      while (index < end && '/' == path.charAt(index)) ++index;
+      start = index;
+    }
+    return sb.append(path, start, index);
+  }
+
+  private static String join (CharSequence[] cs, int start, int end, String prefix) {
+    final StringBuilder sb = new StringBuilder();
+    while (start < end) {
+      sb.append(prefix).append(cs[start++]);
+      prefix = "/";
+    }
+    return sb.toString();
+  }
+
+  private static abstract class NameIterator<T> implements Iterator<T> {
+
+    private final String path;
+    private final short[] offsets;
+    private final int end;
+    private int index;
+
+    public NameIterator (String path, short[] offsets, int count) {
+      this.path = path;
+      this.offsets = offsets;
+      this.end = count - 1;
+    }
+
+    @Override
+    public final boolean hasNext () {
+      return index <= end;
+    }
+
+    @Override
+    public final T next () {
+      final int i = index;
+      if (i > end)
+        throw new NoSuchElementException();
+      ++index;
+      return next(
+          path,
+          offsets[i] & 0xFFFF,
+          (i < end) ? (offsets[i + 1] & 0xFFFF) - 1 : path.length());
+    }
+
+    @Override
+    public final void remove () {
+      throw new UnsupportedOperationException();
+    }
+
+    protected abstract T next (String path, int start, int end);
+
+  } // class NameIterator
+
+}
diff --git a/mirai-console/backend/mirai-console/src/data/PluginDataStorage.kt b/mirai-console/backend/mirai-console/src/data/PluginDataStorage.kt
index a4a6321b2a..1c0c1aa9e2 100644
--- a/mirai-console/backend/mirai-console/src/data/PluginDataStorage.kt
+++ b/mirai-console/backend/mirai-console/src/data/PluginDataStorage.kt
@@ -17,7 +17,7 @@ import net.mamoe.mirai.console.plugin.jvm.JvmPlugin
 import net.mamoe.mirai.console.plugin.jvm.JvmPluginLoader
 import net.mamoe.mirai.console.util.ConsoleExperimentalApi
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 
 /**
  * [数据对象][PluginData] 存储仓库.
diff --git a/mirai-console/backend/mirai-console/src/internal/auth/ConsoleSecretsCalculator.kt b/mirai-console/backend/mirai-console/src/internal/auth/ConsoleSecretsCalculator.kt
index 73f0395c99..5685c935f0 100644
--- a/mirai-console/backend/mirai-console/src/internal/auth/ConsoleSecretsCalculator.kt
+++ b/mirai-console/backend/mirai-console/src/internal/auth/ConsoleSecretsCalculator.kt
@@ -13,12 +13,13 @@ import net.mamoe.mirai.utils.SecretsProtection
 import net.mamoe.mirai.utils.lateinitMutableProperty
 import java.io.ByteArrayOutputStream
 import java.io.DataOutputStream
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import java.util.*
-import kotlin.io.path.createDirectories
-import kotlin.io.path.isRegularFile
-import kotlin.io.path.readBytes
-import kotlin.io.path.writeBytes
+import com.llamalab.safs.kotlin.io.path.createDirectories
+import com.llamalab.safs.kotlin.io.path.readBytes
+import com.llamalab.safs.kotlin.io.path.writeBytes
+
+import com.llamalab.safs.kotlin.io.path.isRegularFile
 
 internal class ConsoleSecretsCalculator(
     private val file: Path,
diff --git a/mirai-console/backend/mirai-console/src/internal/data/MultiFilePluginDataStorageImpl.kt b/mirai-console/backend/mirai-console/src/internal/data/MultiFilePluginDataStorageImpl.kt
index 4048c24391..be5cb0410d 100644
--- a/mirai-console/backend/mirai-console/src/internal/data/MultiFilePluginDataStorageImpl.kt
+++ b/mirai-console/backend/mirai-console/src/internal/data/MultiFilePluginDataStorageImpl.kt
@@ -24,7 +24,7 @@ import net.mamoe.mirai.utils.MiraiLogger
 import net.mamoe.mirai.utils.currentTimeMillis
 import net.mamoe.yamlkt.Yaml
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 
 @Suppress("RedundantVisibilityModifier") // might be public in the future
 internal open class MultiFilePluginDataStorageImpl(
diff --git a/mirai-console/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt b/mirai-console/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt
index 15ac1bad39..ce5cab09e2 100644
--- a/mirai-console/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt
+++ b/mirai-console/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt
@@ -31,7 +31,7 @@ import net.mamoe.mirai.console.util.ConsoleExperimentalApi
 import net.mamoe.mirai.utils.*
 import net.mamoe.yamlkt.Yaml
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import java.util.concurrent.ConcurrentHashMap
 import kotlin.coroutines.CoroutineContext
 
diff --git a/mirai-console/backend/mirai-console/src/internal/plugin/JvmPluginInternal.kt b/mirai-console/backend/mirai-console/src/internal/plugin/JvmPluginInternal.kt
index e4d76fee60..6b62a8631d 100644
--- a/mirai-console/backend/mirai-console/src/internal/plugin/JvmPluginInternal.kt
+++ b/mirai-console/backend/mirai-console/src/internal/plugin/JvmPluginInternal.kt
@@ -41,7 +41,7 @@ import net.mamoe.mirai.utils.MiraiLogger
 import net.mamoe.mirai.utils.safeCast
 import java.io.File
 import java.io.InputStream
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import java.util.*
 import java.util.concurrent.locks.ReentrantLock
 import kotlin.coroutines.CoroutineContext
diff --git a/mirai-console/backend/mirai-console/src/internal/plugin/NotYetLoadedJvmPlugin.kt b/mirai-console/backend/mirai-console/src/internal/plugin/NotYetLoadedJvmPlugin.kt
index aae67fb745..9f743f828d 100644
--- a/mirai-console/backend/mirai-console/src/internal/plugin/NotYetLoadedJvmPlugin.kt
+++ b/mirai-console/backend/mirai-console/src/internal/plugin/NotYetLoadedJvmPlugin.kt
@@ -19,7 +19,7 @@ import net.mamoe.mirai.console.plugin.jvm.JvmPluginDescription
 import net.mamoe.mirai.utils.MiraiLogger
 import java.io.File
 import java.io.InputStream
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import kotlin.coroutines.CoroutineContext
 
 internal abstract class NotYetLoadedJvmPlugin(
diff --git a/mirai-console/backend/mirai-console/src/internal/plugin/PluginManagerImpl.kt b/mirai-console/backend/mirai-console/src/internal/plugin/PluginManagerImpl.kt
index 0cb215d6ea..cd7471bd58 100644
--- a/mirai-console/backend/mirai-console/src/internal/plugin/PluginManagerImpl.kt
+++ b/mirai-console/backend/mirai-console/src/internal/plugin/PluginManagerImpl.kt
@@ -30,7 +30,7 @@ import net.mamoe.mirai.console.plugin.name
 import net.mamoe.mirai.console.util.SemVersion
 import net.mamoe.mirai.utils.*
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 import java.util.concurrent.CopyOnWriteArrayList
 import kotlin.coroutines.CoroutineContext
 
diff --git a/mirai-console/backend/mirai-console/src/internal/shutdown/ShutdownDaemon.kt b/mirai-console/backend/mirai-console/src/internal/shutdown/ShutdownDaemon.kt
index 24d9ec7c72..a4a3e471b6 100644
--- a/mirai-console/backend/mirai-console/src/internal/shutdown/ShutdownDaemon.kt
+++ b/mirai-console/backend/mirai-console/src/internal/shutdown/ShutdownDaemon.kt
@@ -24,7 +24,7 @@ import java.io.FileOutputStream
 import java.io.PrintStream
 import java.lang.management.ManagementFactory
 import java.lang.reflect.Method
-import java.nio.file.Paths
+import com.llamalab.safs.Paths
 import java.time.Instant
 import java.time.ZoneOffset
 import java.util.*
@@ -33,7 +33,7 @@ import java.util.concurrent.Executors
 import java.util.concurrent.ThreadFactory
 import java.util.concurrent.atomic.AtomicBoolean
 import java.util.concurrent.atomic.AtomicInteger
-import kotlin.io.path.writeText
+import com.llamalab.safs.kotlin.io.path.writeText
 
 internal object ShutdownDaemon {
     @Suppress("RemoveRedundantQualifierName")
@@ -110,6 +110,7 @@ internal object ShutdownDaemon {
         bridge.mainLogger.debug { "SHUTDOWN DAEMON STARTED........." }
     }
 
+    @OptIn(ConsoleInternalApi::class)
     @Suppress("MemberVisibilityCanBePrivate")
     fun dumpCrashReport(saveError: Boolean) {
         val isAndroidSystem = kotlin.runCatching { Class.forName("android.util.Log") }.isSuccess
diff --git a/mirai-console/backend/mirai-console/src/plugin/PluginFileExtensions.kt b/mirai-console/backend/mirai-console/src/plugin/PluginFileExtensions.kt
index a4e134e5d1..338a775d93 100644
--- a/mirai-console/backend/mirai-console/src/plugin/PluginFileExtensions.kt
+++ b/mirai-console/backend/mirai-console/src/plugin/PluginFileExtensions.kt
@@ -13,7 +13,7 @@ import net.mamoe.mirai.console.data.PluginConfig
 import net.mamoe.mirai.console.data.PluginData
 import net.mamoe.mirai.console.plugin.jvm.JvmPlugin
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 
 
 /**
diff --git a/mirai-console/backend/mirai-console/src/plugin/PluginManager.kt b/mirai-console/backend/mirai-console/src/plugin/PluginManager.kt
index 1207fffa97..fb7c760bd7 100644
--- a/mirai-console/backend/mirai-console/src/plugin/PluginManager.kt
+++ b/mirai-console/backend/mirai-console/src/plugin/PluginManager.kt
@@ -17,7 +17,7 @@ import net.mamoe.mirai.console.plugin.description.PluginDescription
 import net.mamoe.mirai.console.plugin.loader.PluginLoader
 import net.mamoe.mirai.utils.NotStableForInheritance
 import java.io.File
-import java.nio.file.Path
+import com.llamalab.safs.Path
 
 /**
  * 插件管理器.