diff --git a/build-tools/src/main/kotlin/org/projectnessie/cel/tools/plugins/ReflectionConfigPlugin.kt b/build-tools/src/main/kotlin/org/projectnessie/cel/tools/plugins/ReflectionConfigPlugin.kt
index e39d1b33..52c69e66 100644
--- a/build-tools/src/main/kotlin/org/projectnessie/cel/tools/plugins/ReflectionConfigPlugin.kt
+++ b/build-tools/src/main/kotlin/org/projectnessie/cel/tools/plugins/ReflectionConfigPlugin.kt
@@ -18,6 +18,7 @@ package org.projectnessie.cel.tools.plugins
 
 import org.gradle.api.Plugin
 import org.gradle.api.Project
+import org.gradle.api.UnknownTaskException
 import org.gradle.api.plugins.JavaLibraryPlugin
 import org.gradle.api.tasks.SourceSet
 import org.gradle.api.tasks.SourceSetContainer
@@ -58,6 +59,11 @@ class ReflectionConfigPlugin : Plugin<Project> {
       tasks.named(processResourcesTaskName) {
         dependsOn(genRefCfg)
       }
+      try {
+        tasks.named(sourcesJarTaskName) {
+          dependsOn(genRefCfg)
+        }
+      } catch (ignore: UnknownTaskException) { null }
     }
   }
 }
diff --git a/conformance/build.gradle.kts b/conformance/build.gradle.kts
index 739ca3a2..f2ed340b 100644
--- a/conformance/build.gradle.kts
+++ b/conformance/build.gradle.kts
@@ -69,3 +69,8 @@ protobuf {
         artifact = "com.google.protobuf:protoc:$versionProtobuf"
     }
 }
+
+// The protobuf-plugin should ideally do this
+tasks.named<Jar>("sourcesJar") {
+    dependsOn(tasks.named("generateProto"))
+}
diff --git a/core/build.gradle.kts b/core/build.gradle.kts
index 071a2d33..e5d4208e 100644
--- a/core/build.gradle.kts
+++ b/core/build.gradle.kts
@@ -59,6 +59,8 @@ tasks.register<Jar>("testJar") {
     val testClasses = tasks.getByName<JavaCompile>("compileTestJava")
     val baseJar = tasks.getByName<Jar>("jar")
     from(testClasses.destinationDirectory)
+    dependsOn(testClasses)
+    dependsOn(tasks.named("processTestResources"))
     archiveBaseName.set(baseJar.archiveBaseName)
     destinationDirectory.set(baseJar.destinationDirectory)
     archiveClassifier.set("tests")
diff --git a/generated-antlr/build.gradle.kts b/generated-antlr/build.gradle.kts
index b86885ce..c7a598c8 100644
--- a/generated-antlr/build.gradle.kts
+++ b/generated-antlr/build.gradle.kts
@@ -27,3 +27,8 @@ dependencies {
     antlr("org.antlr:antlr4:$versionAntlr") // TODO remove from runtime-classpath *sigh*
     implementation("org.antlr:antlr4-runtime:$versionAntlr")
 }
+
+// The antlr-plugin should ideally do this
+tasks.named<Jar>("sourcesJar") {
+    dependsOn(tasks.named("generateGrammarSource"))
+}
diff --git a/generated-pb/build.gradle.kts b/generated-pb/build.gradle.kts
index 8ccb34a7..1f454510 100644
--- a/generated-pb/build.gradle.kts
+++ b/generated-pb/build.gradle.kts
@@ -86,6 +86,8 @@ tasks.register<Jar>("testJar") {
     val testClasses = tasks.getByName<JavaCompile>("compileTestJava")
     val baseJar = tasks.getByName<Jar>("jar")
     from(testClasses.destinationDirectory, project.buildDir.resolve("resources/test"))
+    dependsOn(testClasses)
+    dependsOn(tasks.named("processTestResources"))
     archiveBaseName.set(baseJar.archiveBaseName)
     destinationDirectory.set(baseJar.destinationDirectory)
     archiveClassifier.set("tests")
@@ -96,3 +98,8 @@ artifacts {
         builtBy(testJar)
     }
 }
+
+// The protobuf-plugin should ideally do this
+tasks.named<Jar>("sourcesJar") {
+    dependsOn(tasks.named("generateProto"))
+}