diff --git a/buildScripts/tests.ant.xml b/buildScripts/tests.ant.xml
index 630bac42e..ade6fbffe 100644
--- a/buildScripts/tests.ant.xml
+++ b/buildScripts/tests.ant.xml
@@ -220,7 +220,7 @@ This buildfile is part of projectlombok.org. It takes care of compiling and runn
 	
 	<target name="test.eclipse-202312" depends="test.compile, test.formatter.compile" description="runs the tests on your default VM, testing the 2023-12 release of eclipse">
 		<fetchdep.eclipse version="202312" />
-		<test.eclipse-X version="202312" compiler.compliance.level="17" />
+		<test.eclipse-X version="202312" />
 	</target>
 	
 	<target name="test.eclipse-I-build" depends="test.compile, test.formatter.compile, deps.rtstubs18, compile.support" description="runs the tests on your default VM, testing the latest integration build of eclipse">
diff --git a/test/transform/resource/after-ecj/BuilderSingularSequencedCollections.java b/test/transform/resource/after-ecj/BuilderSingularSequencedCollections.java
new file mode 100644
index 000000000..5c477ff45
--- /dev/null
+++ b/test/transform/resource/after-ecj/BuilderSingularSequencedCollections.java
@@ -0,0 +1,132 @@
+// version 21:
+import java.util.SequencedCollection;
+import java.util.SequencedMap;
+import java.util.SequencedSet;
+import lombok.Builder;
+import lombok.Singular;
+@Builder class BuilderSingularSequencedCollections<T, K, V> {
+  public static @java.lang.SuppressWarnings("all") class BuilderSingularSequencedCollectionsBuilder<T, K, V> {
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<T> sequencedCollection;
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<K> sequencedMap$key;
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<V> sequencedMap$value;
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<T> sequencedSet;
+    @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollectionsBuilder() {
+      super();
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> col(final T col) {
+      if ((this.sequencedCollection == null))
+          this.sequencedCollection = new java.util.ArrayList<T>();
+      this.sequencedCollection.add(col);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> sequencedCollection(final java.util.Collection<? extends T> sequencedCollection) {
+      if ((sequencedCollection == null))
+          {
+            throw new java.lang.NullPointerException("sequencedCollection cannot be null");
+          }
+      if ((this.sequencedCollection == null))
+          this.sequencedCollection = new java.util.ArrayList<T>();
+      this.sequencedCollection.addAll(sequencedCollection);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> clearSequencedCollection() {
+      if ((this.sequencedCollection != null))
+          this.sequencedCollection.clear();
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> map(final K mapKey, final V mapValue) {
+      if ((this.sequencedMap$key == null))
+          {
+            this.sequencedMap$key = new java.util.ArrayList<K>();
+            this.sequencedMap$value = new java.util.ArrayList<V>();
+          }
+      this.sequencedMap$key.add(mapKey);
+      this.sequencedMap$value.add(mapValue);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> sequencedMap(final java.util.Map<? extends K, ? extends V> sequencedMap) {
+      if ((sequencedMap == null))
+          {
+            throw new java.lang.NullPointerException("sequencedMap cannot be null");
+          }
+      if ((this.sequencedMap$key == null))
+          {
+            this.sequencedMap$key = new java.util.ArrayList<K>();
+            this.sequencedMap$value = new java.util.ArrayList<V>();
+          }
+      for (java.util.Map.Entry<? extends K, ? extends V> $lombokEntry : sequencedMap.entrySet())
+        {
+          this.sequencedMap$key.add($lombokEntry.getKey());
+          this.sequencedMap$value.add($lombokEntry.getValue());
+        }
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> clearSequencedMap() {
+      if ((this.sequencedMap$key != null))
+          {
+            this.sequencedMap$key.clear();
+            this.sequencedMap$value.clear();
+          }
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> set(final T set) {
+      if ((this.sequencedSet == null))
+          this.sequencedSet = new java.util.ArrayList<T>();
+      this.sequencedSet.add(set);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> sequencedSet(final java.util.Collection<? extends T> sequencedSet) {
+      if ((sequencedSet == null))
+          {
+            throw new java.lang.NullPointerException("sequencedSet cannot be null");
+          }
+      if ((this.sequencedSet == null))
+          this.sequencedSet = new java.util.ArrayList<T>();
+      this.sequencedSet.addAll(sequencedSet);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> clearSequencedSet() {
+      if ((this.sequencedSet != null))
+          this.sequencedSet.clear();
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections<T, K, V> build() {
+      java.util.SequencedCollection<T> sequencedCollection;
+      switch (((this.sequencedCollection == null) ? 0 : this.sequencedCollection.size())) {
+      case 0 :
+          sequencedCollection = java.util.Collections.emptyList();
+          break;
+      case 1 :
+          sequencedCollection = java.util.Collections.singletonList(this.sequencedCollection.get(0));
+          break;
+      default :
+          sequencedCollection = java.util.Collections.unmodifiableList(new java.util.ArrayList<T>(this.sequencedCollection));
+      }
+      java.util.SequencedMap<K, V> sequencedMap = new java.util.LinkedHashMap<K, V>();
+      if ((this.sequencedMap$key != null))
+          for (int $i = 0;; ($i < ((this.sequencedMap$key == null) ? 0 : this.sequencedMap$key.size())); $i ++)
+            sequencedMap.put(this.sequencedMap$key.get($i), this.sequencedMap$value.get($i));
+      sequencedMap = java.util.Collections.unmodifiableSequencedMap(sequencedMap);
+      java.util.SequencedSet<T> sequencedSet = new java.util.LinkedHashSet<T>();
+      if ((this.sequencedSet != null))
+          sequencedSet.addAll(this.sequencedSet);
+      sequencedSet = java.util.Collections.unmodifiableSequencedSet(sequencedSet);
+      return new BuilderSingularSequencedCollections<T, K, V>(sequencedCollection, sequencedMap, sequencedSet);
+    }
+    public @java.lang.Override @java.lang.SuppressWarnings("all") java.lang.String toString() {
+      return (((((((("BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder(sequencedCollection=" + this.sequencedCollection) + ", sequencedMap$key=") + this.sequencedMap$key) + ", sequencedMap$value=") + this.sequencedMap$value) + ", sequencedSet=") + this.sequencedSet) + ")");
+    }
+  }
+  private @Singular("col") SequencedCollection<T> sequencedCollection;
+  private @Singular("map") SequencedMap<K, V> sequencedMap;
+  private @Singular("set") SequencedSet<T> sequencedSet;
+  @java.lang.SuppressWarnings("all") BuilderSingularSequencedCollections(final SequencedCollection<T> sequencedCollection, final SequencedMap<K, V> sequencedMap, final SequencedSet<T> sequencedSet) {
+    super();
+    this.sequencedCollection = sequencedCollection;
+    this.sequencedMap = sequencedMap;
+    this.sequencedSet = sequencedSet;
+  }
+  public static @java.lang.SuppressWarnings("all") <T, K, V>BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V> builder() {
+    return new BuilderSingularSequencedCollections.BuilderSingularSequencedCollectionsBuilder<T, K, V>();
+  }
+}
\ No newline at end of file
diff --git a/test/transform/resource/messages-ecj/BuilderSingularSequencedCollections.java.messages b/test/transform/resource/messages-ecj/BuilderSingularSequencedCollections.java.messages
new file mode 100644
index 000000000..915eaabf9
--- /dev/null
+++ b/test/transform/resource/messages-ecj/BuilderSingularSequencedCollections.java.messages
@@ -0,0 +1,12 @@
+3 The import java.util.SequencedCollection cannot be resolved
+4 The import java.util.SequencedMap cannot be resolved
+5 The import java.util.SequencedSet cannot be resolved
+10 SequencedCollection cannot be resolved to a type
+10 SequencedMap cannot be resolved to a type
+10 SequencedSet cannot be resolved to a type
+10 java.util.SequencedCollection cannot be resolved to a type
+10 java.util.SequencedMap cannot be resolved to a type
+10 java.util.SequencedSet cannot be resolved to a type
+12 SequencedCollection cannot be resolved to a type
+13 SequencedMap cannot be resolved to a type
+14 SequencedSet cannot be resolved to a type
\ No newline at end of file