diff --git a/src/core/lombok/eclipse/handlers/HandleBuilder.java b/src/core/lombok/eclipse/handlers/HandleBuilder.java
index 64a3fa9..6ebaaaf 100755
--- a/src/core/lombok/eclipse/handlers/HandleBuilder.java
+++ b/src/core/lombok/eclipse/handlers/HandleBuilder.java
@@ -493,10 +493,13 @@ public class HandleBuilder extends EclipseAnnotationHandler<Builder> {
 		if (!checkBuilderClassNameAnnotationConflict("Builder", "lombok.Builder", job.builderClassName, ast, annotationNode)) return;
 		
 		if (fillParametersFrom != null) {
-			for (EclipseNode param : fillParametersFrom.down()) {
-				if (param.getKind() != Kind.ARGUMENT) continue;
+			// ECJ has not populated the implicit arguments of a compact record constructor yet.
+			boolean compactConstructor = parent.get() instanceof ConstructorDeclaration
+				&& isRecord(job.parentType) && (parent.get().bits & IsCanonicalConstructor) != 0;
+			for (EclipseNode param : (compactConstructor ? job.parentType : fillParametersFrom).down()) {
+				if (compactConstructor ? !isRecordField(param) : param.getKind() != Kind.ARGUMENT) continue;
 				BuilderFieldData bfd = new BuilderFieldData();
-				Argument arg = (Argument) param.get();
+				AbstractVariableDeclaration arg = (AbstractVariableDeclaration) param.get();
 				
 				Annotation[] copyableAnnotations = findCopyableAnnotations(param);