diff --git a/eo-runtime/src/main/eo/org/eolang/bytes.eo b/eo-runtime/src/main/eo/org/eolang/bytes.eo
index f88150abab..ac9a474ecf 100644
--- a/eo-runtime/src/main/eo/org/eolang/bytes.eo
+++ b/eo-runtime/src/main/eo/org/eolang/bytes.eo
@@ -35,7 +35,6 @@
   data > @
   $ > as-bytes
   $.eq 01- > as-bool
-  string $ > as-string
 
   # Turn this chain of eight bytes into a number.
   # If there are less or more than eight bytes, there will
diff --git a/eo-runtime/src/main/eo/org/eolang/fs/dir.eo b/eo-runtime/src/main/eo/org/eolang/fs/dir.eo
index 3077d23dfc..fc64d655d5 100644
--- a/eo-runtime/src/main/eo/org/eolang/fs/dir.eo
+++ b/eo-runtime/src/main/eo/org/eolang/fs/dir.eo
@@ -90,7 +90,8 @@
   [] > tmpfile
     if. > @
       ^.exists
-      QQ.fs.file touch.as-bytes.as-string
+      QQ.fs.file
+        string touch.as-bytes
       error
         sprintf
           "Directory %s does not exist, can't create temporary file"
diff --git a/eo-runtime/src/main/eo/org/eolang/fs/file.eo b/eo-runtime/src/main/eo/org/eolang/fs/file.eo
index fc31319aed..dcbbd65757 100644
--- a/eo-runtime/src/main/eo/org/eolang/fs/file.eo
+++ b/eo-runtime/src/main/eo/org/eolang/fs/file.eo
@@ -78,7 +78,8 @@
 
   # Move current file to `target`, making and returning a new `file` from it.
   [target] > moved
-    QQ.fs.file move.as-bytes.as-string > @
+    QQ.fs.file > @
+      string move.as-bytes
 
     # Tries to move file from `^.path` to `target`
     # and returns path of moved file as `string`.
diff --git a/eo-runtime/src/main/eo/org/eolang/fs/path.eo b/eo-runtime/src/main/eo/org/eolang/fs/path.eo
index 88a61efd62..e6e05bb7e1 100644
--- a/eo-runtime/src/main/eo/org/eolang/fs/path.eo
+++ b/eo-runtime/src/main/eo/org/eolang/fs/path.eo
@@ -43,7 +43,7 @@
   # Utility object that joins given `tuple` of paths with current OS separator
   # and normalizes result path.
   [paths] > joined
-    as-string. > joined-path
+    string > joined-path
       as-bytes.
         joined.
           text ^.separator
@@ -132,11 +132,10 @@
               --
       determined. > @
         ^.^.posix
-          as-string.
-            if.
-              normalized.eq "//"
-              "/"
-              normalized
+          if.
+            normalized.eq "//"
+            "/"
+            string normalized
 
     # Resolves `other` path against `^.uri` and returns as new `path` from it.
     # The original `uri` and resolving `other` may be:
@@ -269,7 +268,7 @@
     "\\" > separator
     determined. > @
       validated
-        as-string.
+        string
           as-bytes.
             validated.separated-correctly
               uri
@@ -397,11 +396,10 @@
                 --
         determined. > @
           ^.^.validated
-            as-string.
-              if.
-                normalized.eq "\\\\"
-                ^.separator
-                normalized
+            if.
+              normalized.eq "\\\\"
+              ^.separator
+              string normalized
 
       # Resolves `other` path against `^.uri` and returns as new `path` from it.
       # Original `uri` and `other` path for resolving may be:
diff --git a/eo-runtime/src/main/eo/org/eolang/txt/text.eo b/eo-runtime/src/main/eo/org/eolang/txt/text.eo
index d7da838bef..c70255859f 100644
--- a/eo-runtime/src/main/eo/org/eolang/txt/text.eo
+++ b/eo-runtime/src/main/eo/org/eolang/txt/text.eo
@@ -108,17 +108,17 @@
     ^.origin > delimiter!
     items.at 0 > first
     items.length > len!
+    if. > not-empty!
+      1.eq len
+      first
+      concat.
+        first.as-bytes
+        with-delimiter "".as-bytes 1
     text > @
       if.
         0.eq len
         ""
-        if.
-          1.eq len
-          first
-          as-string.
-            concat.
-              first.as-bytes
-              with-delimiter "".as-bytes 1
+        string not-empty
 
     [acc index] > with-delimiter
       if. > @
@@ -146,7 +146,7 @@
         if.
           0.eq amount
           ""
-          as-string.
+          string
             rec-repeated bts 1
 
     [accum index] > rec-repeated
@@ -249,7 +249,7 @@
       number ascii-a
       ascii "A"
     text > @
-      as-string.
+      string
         reduced.
           list
             bytes-as-array
@@ -282,7 +282,7 @@
     ^.up-cased.ascii "Z" > ascii-z
     ^.up-cased.ascii "A" > ascii-a
     text > @
-      as-string.
+      string
         reduced.
           list
             bytes-as-array
@@ -349,7 +349,7 @@
                 block.from.minus start
             ^.replacement
           block.to
-        as-string.
+        string
           accum.concat
             ^.reinit.slice
               start
@@ -404,7 +404,7 @@
       0.eq others.length
       ^
       text
-        as-string.
+        string
           reduced.
             list others
             ^.origin.as-bytes
diff --git a/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo b/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo
index 97ba7c7c7d..95da0e2396 100644
--- a/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo
@@ -55,7 +55,7 @@
 # This unit test is supposed to check the functionality of the corresponding object.
 [] > turns-bytes-into-a-string
   eq. > @
-    as-string.
+    string
       E4-BD-A0-E5-A5-BD-2C-20-D0-B4-D1-80-D1-83-D0-B3-21
     "你好, друг!"
 
@@ -351,8 +351,7 @@
     "hello ".as-bytes
     "world".as-bytes
   eq. > @
-    as-string.
-      s-bytes
+    string s-bytes
     "hello world"
 
 # This unit test is supposed to check the functionality of the corresponding object.
diff --git a/eo-runtime/src/test/java/EOorg/EOeolang/EObytesEOconcatTest.java b/eo-runtime/src/test/java/EOorg/EOeolang/EObytesEOconcatTest.java
index ac572a99b8..9d7a5abe79 100644
--- a/eo-runtime/src/test/java/EOorg/EOeolang/EObytesEOconcatTest.java
+++ b/eo-runtime/src/test/java/EOorg/EOeolang/EObytesEOconcatTest.java
@@ -50,13 +50,14 @@ final class EObytesEOconcatTest {
     void concatenatesBytes() {
         final Phi current = new Data.ToPhi("привет ").take("as-bytes");
         final Phi provided = new Data.ToPhi("mr. ㄤㄠ!").take("as-bytes");
-        final Phi phi = new PhMethod(
+        final Phi phi = new PhWith(
+            Phi.Φ.take("org.eolang.string"),
+            0,
             new PhWith(
                 current.take("concat").copy(),
                 "b",
                 provided
-            ),
-            "as-string"
+            )
         );
         MatcherAssert.assertThat(
             AtCompositeTest.TO_ADD_MESSAGE,