Move to truffle object model

buildSrc/src/main/kotlin/NativeImageBuild.kt

@@ -55,8 +55,7 @@ abstract class NativeImageBuild : DefaultTask() {
 
   @get:Inject protected abstract val execOperations: ExecOperations
 
-  private val graalVm: Provider<BuildInfo.GraalVm> =
+  private val graalVm: Provider<BuildInfo.GraalVm> = arch.map { a ->
-    arch.map { a ->
     when (a) {
       Architecture.AMD64 -> buildInfo.graalVmAmd64
       Architecture.AARCH64 -> buildInfo.graalVmAarch64
@@ -132,7 +131,7 @@ abstract class NativeImageBuild : DefaultTask() {
         add(imageName.get())
         // the actual limit (currently) used by native-image is this number + 1400 (idea is to
         // compensate for Truffle's own nodes)
-        add("-H:MaxRuntimeCompileMethods=1800")
+        add("-H:MaxRuntimeCompileMethods=2000")
         add("-H:+EnforceMaxRuntimeCompileMethods")
         add("--enable-url-protocols=http,https")
         add("-H:+ReportExceptionStackTraces")
@@ -151,8 +150,7 @@ abstract class NativeImageBuild : DefaultTask() {
         }
         // native-image rejects non-existing class path entries -> filter
         add("--class-path")
-        val pathInput =
+        val pathInput = classpath.filter {
-          classpath.filter {
           it.exists() && !exclusions.any { exclude -> it.name.contains(exclude) }
         }
         add(pathInput.asPath)

pkl-core/src/main/java/org/pkl/core/ast/expression/member/ReadLocalPropertyNode.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,10 +22,20 @@ import com.oracle.truffle.api.nodes.ExplodeLoop;
 import com.oracle.truffle.api.source.SourceSection;
 import org.pkl.core.ast.ExpressionNode;
 import org.pkl.core.ast.member.ObjectMember;
-import org.pkl.core.runtime.VmObjectLike;
+import org.pkl.core.runtime.VmObject;
 import org.pkl.core.runtime.VmUtils;
 
-/** Reads a local non-constant property that is known to exist in the lexical scope of this node. */
+/**
+ * Reads a local non-constant property that is known to exist in the lexical scope of this node.
+ *
+ * <p>Local property values are cached using the ObjectMember as the key (identity-based) rather
+ * than the property name. This is necessary because the same property name can exist at different
+ * declaration sites in an amends chain, and we need to distinguish between them for correct
+ * late-binding semantics.
+ *
+ * <p>The cache is stored in a separate IdentityHashMap in VmObject (not in the DynamicObject
+ * storage) to avoid shape transitions that would destroy cache locality.
+ */
 public final class ReadLocalPropertyNode extends ExpressionNode {
   private final ObjectMember property;
   private final int levelsUp;
@@ -63,15 +73,17 @@ public final class ReadLocalPropertyNode extends ExpressionNode {
       owner = owner.getEnclosingOwner();
     }
 
-    assert receiver instanceof VmObjectLike
+    assert receiver instanceof VmObject
         : "Assumption: This node isn't used in Truffle ASTs of `external` pkl.base classes whose values aren't VmObject's.";
 
-    var objReceiver = (VmObjectLike) receiver;
+    // Use the local property cache instead of DynamicObject storage
-    var result = objReceiver.getCachedValue(property);
+    // to avoid shape transitions from ObjectMember keys
+    var objReceiver = (VmObject) receiver;
+    var result = objReceiver.getLocalCachedValue(property);
 
     if (result == null) {
       result = callNode.call(objReceiver, owner, property.getName());
-      objReceiver.setCachedValue(property, result);
+      objReceiver.setLocalCachedValue(property, result);
     }
 
     return result;

pkl-core/src/main/java/org/pkl/core/ast/expression/member/ReadPropertyNode.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,9 +19,12 @@ import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.dsl.*;
+import com.oracle.truffle.api.dsl.Cached.Shared;
+import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.DirectCallNode;
 import com.oracle.truffle.api.nodes.IndirectCallNode;
 import com.oracle.truffle.api.nodes.NodeInfo;
+import com.oracle.truffle.api.object.DynamicObjectLibrary;
 import com.oracle.truffle.api.source.SourceSection;
 import org.pkl.core.ast.ExpressionNode;
 import org.pkl.core.ast.MemberLookupMode;
@@ -61,6 +64,27 @@ public abstract class ReadPropertyNode extends ExpressionNode {
     this(sourceSection, propertyName, MemberLookupMode.EXPLICIT_RECEIVER, false);
   }
 
+  // Optimized specialization for VmTyped using DynamicObjectLibrary
+  @Specialization
+  protected Object evalTyped(
+      VmTyped receiver,
+      @CachedLibrary(limit = "3") DynamicObjectLibrary objectLibrary,
+      @Cached("create()") @Shared("callNode") IndirectCallNode callNode) {
+
+    checkConst(receiver);
+
+    // fast path: check cache using optimized library access
+    var result = receiver.getCachedValue(propertyName, objectLibrary);
+    if (result != null) return result;
+
+    // slow path: look up member in prototype chain and compute value
+    result = VmUtils.readMemberOrNull(receiver, propertyName, true, callNode);
+    if (result != null) return result;
+
+    CompilerDirectives.transferToInterpreter();
+    throw cannotFindProperty(receiver);
+  }
+
   // This method effectively covers `VmObject receiver` but is implemented in a more
   // efficient way. See:
   // https://www.graalvm.org/22.0/graalvm-as-a-platform/language-implementation-framework/TruffleLibraries/#strategy-2-java-interfaces
@@ -68,7 +92,7 @@ public abstract class ReadPropertyNode extends ExpressionNode {
   protected Object evalObject(
       Object receiver,
       @Cached("getVmObjectSubclassOrNull(receiver)") Class<? extends VmObjectLike> cachedClass,
-      @Cached("create()") IndirectCallNode callNode) {
+      @Cached("create()") @Shared("callNode") IndirectCallNode callNode) {
 
     var object = cachedClass.cast(receiver);
     checkConst(object);

pkl-core/src/main/java/org/pkl/core/runtime/PklShape.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright © 2026 Apple Inc. and the Pkl project authors. All rights reserved.
+ *
+ * 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
+ *
+ *     https://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 org.pkl.core.runtime;
+
+import com.oracle.truffle.api.object.Shape;
+
+/** Factory for Truffle {@link Shape} instances used by Pkl objects. */
+public final class PklShape {
+
+  /** The root shape for all Pkl object instances. */
+  private static final Shape ROOT_SHAPE = Shape.newBuilder().build();
+
+  private PklShape() {}
+
+  /**
+   * Returns the root shape for Pkl objects.
+   *
+   * <p>This is the base shape from which all instance shapes derive. Properties are added
+   * dynamically as values are cached via {@link
+   * com.oracle.truffle.api.object.DynamicObjectLibrary#put}.
+   */
+  public static Shape getRootShape() {
+    return ROOT_SHAPE;
+  }
+}

pkl-core/src/main/java/org/pkl/core/runtime/TestRunner.java

@@ -104,7 +104,7 @@ public final class TestRunner {
                   if (factValue == Boolean.FALSE) {
                     if (PowerAssertions.isEnabled()) {
                       try (var valueTracker = valueTrackerFactory.create()) {
-                        listing.cachedValues.clear();
+                        listing.cleanAllCachedValues();
                         VmUtils.readMember(listing, idx);
                         var failure =
                             factFailure(

pkl-core/src/main/java/org/pkl/core/runtime/VmBytes.java

@@ -29,7 +29,7 @@ import org.pkl.core.util.ByteArrayUtils;
 import org.pkl.core.util.Nullable;
 
 @ValueType
-public final class VmBytes extends VmValue implements Iterable<Long> {
+public final class VmBytes implements VmValue, Iterable<Long> {
 
   private @Nullable VmList vmList;
   private @Nullable String base64;

pkl-core/src/main/java/org/pkl/core/runtime/VmClass.java

@@ -19,6 +19,8 @@ import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.dsl.Idempotent;
 import com.oracle.truffle.api.frame.FrameDescriptor;
+import com.oracle.truffle.api.nodes.IndirectCallNode;
+import com.oracle.truffle.api.object.Shape;
 import com.oracle.truffle.api.source.SourceSection;
 import java.util.*;
 import java.util.function.*;
@@ -43,7 +45,7 @@ import org.pkl.core.util.Nullable;
 // The currently implemented (and likely insufficient) solution is to
 // * deeply force standard library modules at initialization time.
 // * ensure that any further mutation (e.g., lazy initialization in VmClass) is thread-safe.
-public final class VmClass extends VmValue {
+public final class VmClass implements VmValue {
   private final SourceSection sourceSection;
   private final SourceSection headerSection;
   private final SourceSection @Nullable [] docComment;
@@ -123,6 +125,16 @@ public final class VmClass extends VmValue {
 
   private final Object mapToTypedMembersLock = new Object();
 
+  // Shape for instances of this class - used for Truffle's Dynamic Object Model
+  @LateInit
+  @GuardedBy("instanceShapeLock")
+  private Shape __instanceShape;
+
+  private final Object instanceShapeLock = new Object();
+
+  /** Cached IndirectCallNode for force() operations. */
+  private final IndirectCallNode cachedCallNode = IndirectCallNode.create();
+
   public VmClass(
       SourceSection sourceSection,
       SourceSection headerSection,
@@ -697,6 +709,41 @@ public final class VmClass extends VmValue {
     }
   }
 
+  /**
+   * Returns the Truffle Shape for instances of this class.
+   *
+   * <p>The shape is lazily initialized from the root shape. Instance shapes are used by the Dynamic
+   * Object Model to provide optimized property storage and inline caching for cached property
+   * values.
+   */
+  public Shape getInstanceShape() {
+    synchronized (instanceShapeLock) {
+      if (__instanceShape == null) {
+        __instanceShape = buildInstanceShape();
+      }
+      return __instanceShape;
+    }
+  }
+
+  @TruffleBoundary
+  private Shape buildInstanceShape() {
+    // start with the superclass shape if available, otherwise use root shape
+    if (superclass != null) {
+      return superclass.getInstanceShape();
+    }
+    return PklShape.getRootShape();
+  }
+
+  /**
+   * Returns the cached IndirectCallNode for force() operations.
+   *
+   * <p>This node is shared by all instances of this class and avoids the overhead of {@code
+   * IndirectCallNode.getUncached()} which performs a lookup on every call.
+   */
+  public IndirectCallNode getCachedCallNode() {
+    return cachedCallNode;
+  }
+
   /**
    * Tells if the given property defines a member of this class. Requires a fully initialized
    * inheritance hierarchy.

pkl-core/src/main/java/org/pkl/core/runtime/VmCollection.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,7 +20,7 @@ import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import java.util.Iterator;
 import org.organicdesign.fp.xform.Xform;
 
-public abstract class VmCollection extends VmValue implements Iterable<Object> {
+public abstract class VmCollection implements VmValue, Iterable<Object> {
   public interface Builder<T extends VmCollection> {
     void add(Object element);
 

pkl-core/src/main/java/org/pkl/core/runtime/VmDataSize.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,7 +26,7 @@ import org.pkl.core.util.MathUtils;
 import org.pkl.core.util.Nullable;
 
 @ValueType
-public final class VmDataSize extends VmValue implements Comparable<VmDataSize> {
+public final class VmDataSize implements VmValue, Comparable<VmDataSize> {
   private static final Map<Identifier, DataSizeUnit> UNITS =
       Map.ofEntries(
           entry(Identifier.B, DataSizeUnit.BYTES),

pkl-core/src/main/java/org/pkl/core/runtime/VmDuration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,7 +22,7 @@ import org.pkl.core.util.DurationUtils;
 import org.pkl.core.util.Nullable;
 
 @ValueType
-public final class VmDuration extends VmValue implements Comparable<VmDuration> {
+public final class VmDuration implements VmValue, Comparable<VmDuration> {
   private static final Map<Identifier, DurationUnit> UNITS =
       Map.of(
           Identifier.NS, DurationUnit.NANOS,

pkl-core/src/main/java/org/pkl/core/runtime/VmDynamic.java

@@ -28,6 +28,8 @@ import org.pkl.core.util.EconomicMaps;
 public final class VmDynamic extends VmObject {
   private int cachedRegularMemberCount = -1;
 
+  private final int length;
+
   private static final class EmptyHolder {
     private static final VmDynamic EMPTY =
         new VmDynamic(
@@ -37,8 +39,6 @@ public final class VmDynamic extends VmObject {
             0);
   }
 
-  private final int length;
-
   public static VmDynamic empty() {
     return EmptyHolder.EMPTY;
   }
@@ -48,7 +48,7 @@ public final class VmDynamic extends VmObject {
       VmObject parent,
       UnmodifiableEconomicMap<Object, ObjectMember> members,
       int length) {
-    super(enclosingFrame, Objects.requireNonNull(parent), members);
+    super(PklShape.getRootShape(), enclosingFrame, Objects.requireNonNull(parent), members);
     this.length = length;
   }
 
@@ -75,8 +75,7 @@ public final class VmDynamic extends VmObject {
   @Override
   @TruffleBoundary
   public PObject export() {
-    var properties =
+    var properties = CollectionUtils.<String, Object>newLinkedHashMap(getCachedValueCount());
-        CollectionUtils.<String, Object>newLinkedHashMap(EconomicMaps.size(cachedValues));
 
     iterateMemberValues(
         (key, member, value) -> {
@@ -109,7 +108,7 @@ public final class VmDynamic extends VmObject {
     other.force(false);
     if (getRegularMemberCount() != other.getRegularMemberCount()) return false;
 
-    var cursor = cachedValues.getEntries();
+    var cursor = getCachedValueEntries();
     while (cursor.advance()) {
       Object key = cursor.getKey();
       if (isHiddenOrLocalProperty(key)) continue;
@@ -130,7 +129,7 @@ public final class VmDynamic extends VmObject {
 
     force(false);
     var result = 0;
-    var cursor = cachedValues.getEntries();
+    var cursor = getCachedValueEntries();
 
     while (cursor.advance()) {
       var key = cursor.getKey();
@@ -150,8 +149,9 @@ public final class VmDynamic extends VmObject {
     if (cachedRegularMemberCount != -1) return cachedRegularMemberCount;
 
     var result = 0;
-    for (var key : cachedValues.getKeys()) {
+    var cursor = getCachedValueEntries();
-      if (!isHiddenOrLocalProperty(key)) result += 1;
+    while (cursor.advance()) {
+      if (!isHiddenOrLocalProperty(cursor.getKey())) result += 1;
     }
     cachedRegularMemberCount = result;
     return result;

pkl-core/src/main/java/org/pkl/core/runtime/VmFunction.java

@@ -23,9 +23,14 @@ import org.graalvm.collections.UnmodifiableEconomicMap;
 import org.pkl.core.ast.PklRootNode;
 import org.pkl.core.ast.member.ObjectMember;
 import org.pkl.core.util.EconomicMaps;
+import org.pkl.core.util.EmptyMapCursor;
+import org.pkl.core.util.MapCursor;
 import org.pkl.core.util.Nullable;
 
-public final class VmFunction extends VmObjectLike {
+public final class VmFunction implements VmObjectLike {
+  // Own fields (VmFunction does not extend DynamicObject, so it has its own storage)
+  private final MaterializedFrame enclosingFrame;
+  private @Nullable Object extraStorage;
 
   private final Object thisValue;
   private final int paramCount;
@@ -37,13 +42,28 @@ public final class VmFunction extends VmObjectLike {
       int paramCount,
       PklRootNode rootNode,
       @Nullable Object extraStorage) {
-    super(enclosingFrame);
+    this.enclosingFrame = enclosingFrame;
     this.thisValue = thisValue;
     this.paramCount = paramCount;
     this.rootNode = rootNode;
     this.extraStorage = extraStorage;
   }
 
+  @Override
+  public MaterializedFrame getEnclosingFrame() {
+    return enclosingFrame;
+  }
+
+  @Override
+  public @Nullable Object getExtraStorage() {
+    return extraStorage;
+  }
+
+  @Override
+  public void setExtraStorage(@Nullable Object extraStorage) {
+    this.extraStorage = extraStorage;
+  }
+
   public RootCallTarget getCallTarget() {
     return rootNode.getCallTarget();
   }
@@ -123,17 +143,27 @@ public final class VmFunction extends VmObjectLike {
   }
 
   @Override
-  public boolean iterateMemberValues(MemberValueConsumer consumer) {
+  public MapCursor<Object, Object> getCachedValueEntries() {
+    return EmptyMapCursor.instance();
+  }
+
+  @Override
+  public int getCachedValueCount() {
+    return 0;
+  }
+
+  @Override
+  public boolean iterateMemberValues(VmObjectLike.MemberValueConsumer consumer) {
     return true;
   }
 
   @Override
-  public boolean forceAndIterateMemberValues(ForcedMemberValueConsumer consumer) {
+  public boolean forceAndIterateMemberValues(VmObjectLike.ForcedMemberValueConsumer consumer) {
     return true;
   }
 
   @Override
-  public boolean iterateAlreadyForcedMemberValues(ForcedMemberValueConsumer consumer) {
+  public boolean iterateAlreadyForcedMemberValues(VmObjectLike.ForcedMemberValueConsumer consumer) {
     return true;
   }
 

pkl-core/src/main/java/org/pkl/core/runtime/VmIntSeq.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,7 +25,7 @@ import org.pkl.core.util.Nullable;
 // Some code copied from kotlin.ranges.Progressions, kotlin.ranges.ProgressionIterators,
 // kotlin.internal.ProgressionUtil (Apache 2).
 @ValueType
-public final class VmIntSeq extends VmValue implements Iterable<Long> {
+public final class VmIntSeq implements VmValue, Iterable<Long> {
   public final long start;
   public final long end;
   public final long step;

pkl-core/src/main/java/org/pkl/core/runtime/VmListing.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -87,7 +87,7 @@ public final class VmListing extends VmListingOrMapping {
   @Override
   @TruffleBoundary
   public List<Object> export() {
-    var properties = new ArrayList<>(EconomicMaps.size(cachedValues));
+    var properties = new ArrayList<>(getCachedValueCount());
 
     iterateMemberValues(
         (key, prop, value) -> {
@@ -121,7 +121,7 @@ public final class VmListing extends VmListingOrMapping {
     force(false);
     other.force(false);
 
-    var cursor = cachedValues.getEntries();
+    var cursor = getCachedValueEntries();
     while (cursor.advance()) {
       var key = cursor.getKey();
       if (key instanceof Identifier) continue;
@@ -142,7 +142,7 @@ public final class VmListing extends VmListingOrMapping {
 
     force(false);
     var result = 0;
-    var cursor = cachedValues.getEntries();
+    var cursor = getCachedValueEntries();
 
     while (cursor.advance()) {
       var key = cursor.getKey();

pkl-core/src/main/java/org/pkl/core/runtime/VmListingOrMapping.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,7 +23,6 @@ import org.graalvm.collections.UnmodifiableEconomicMap;
 import org.pkl.core.ast.member.ListingOrMappingTypeCastNode;
 import org.pkl.core.ast.member.ObjectMember;
 import org.pkl.core.ast.type.TypeNode;
-import org.pkl.core.util.EconomicMaps;
 import org.pkl.core.util.Nullable;
 
 public abstract class VmListingOrMapping extends VmObject {
@@ -32,24 +31,24 @@ public abstract class VmListingOrMapping extends VmObject {
   private final @Nullable Object typeCheckReceiver;
   private final @Nullable VmObjectLike typeCheckOwner;
 
-  public VmListingOrMapping(
+  protected VmListingOrMapping(
       MaterializedFrame enclosingFrame,
       @Nullable VmObject parent,
       UnmodifiableEconomicMap<Object, ObjectMember> members) {
-    super(enclosingFrame, parent, members);
+    super(PklShape.getRootShape(), enclosingFrame, parent, members);
     typeCastNode = null;
     typeCheckReceiver = null;
     typeCheckOwner = null;
   }
 
-  public VmListingOrMapping(
+  protected VmListingOrMapping(
       MaterializedFrame enclosingFrame,
       @Nullable VmObject parent,
       UnmodifiableEconomicMap<Object, ObjectMember> members,
       ListingOrMappingTypeCastNode typeCastNode,
       Object typeCheckReceiver,
       VmObjectLike typeCheckOwner) {
-    super(enclosingFrame, parent, members);
+    super(PklShape.getRootShape(), enclosingFrame, parent, members);
     this.typeCastNode = typeCastNode;
     this.typeCheckReceiver = typeCheckReceiver;
     this.typeCheckOwner = typeCheckOwner;
@@ -88,7 +87,7 @@ public abstract class VmListingOrMapping extends VmObject {
   @Override
   @TruffleBoundary
   public final @Nullable Object getCachedValue(Object key) {
-    var result = EconomicMaps.get(cachedValues, key);
+    var result = super.getCachedValue(key);
     // if this object has members, `this[key]` may differ from `parent[key]`, so stop the search
     if (result != null || !members.isEmpty()) return result;
 

pkl-core/src/main/java/org/pkl/core/runtime/VmMap.java

@@ -30,7 +30,7 @@ import org.pkl.core.util.paguro.RrbTree;
 import org.pkl.core.util.paguro.RrbTree.ImRrbt;
 import org.pkl.core.util.paguro.RrbTree.MutRrbt;
 
-public final class VmMap extends VmValue implements Iterable<Map.Entry<Object, Object>> {
+public final class VmMap implements VmValue, Iterable<Map.Entry<Object, Object>> {
   public static final VmMap EMPTY = new VmMap(PersistentHashMap.empty(), RrbTree.empty());
 
   private final ImMap<Object, Object> map;

pkl-core/src/main/java/org/pkl/core/runtime/VmMapping.java

@@ -93,7 +93,7 @@ public final class VmMapping extends VmListingOrMapping {
   @Override
   @TruffleBoundary
   public Map<Object, Object> export() {
-    var properties = CollectionUtils.newLinkedHashMap(EconomicMaps.size(cachedValues));
+    var properties = CollectionUtils.newLinkedHashMap(getCachedValueCount());
 
     iterateMemberValues(
         (key, prop, value) -> {
@@ -128,7 +128,7 @@ public final class VmMapping extends VmListingOrMapping {
     other.force(false);
     if (getLength() != other.getLength()) return false;
 
-    var cursor = cachedValues.getEntries();
+    var cursor = getCachedValueEntries();
     while (cursor.advance()) {
       Object key = cursor.getKey();
       if (key instanceof Identifier) continue;
@@ -149,7 +149,7 @@ public final class VmMapping extends VmListingOrMapping {
 
     force(false);
     var result = 0;
-    var cursor = cachedValues.getEntries();
+    var cursor = getCachedValueEntries();
 
     while (cursor.advance()) {
       var key = cursor.getKey();

pkl-core/src/main/java/org/pkl/core/runtime/VmNull.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,7 +20,7 @@ import org.pkl.core.PNull;
 import org.pkl.core.util.Nullable;
 
 @ValueType
-public final class VmNull extends VmValue {
+public final class VmNull implements VmValue {
   private static final VmNull WITHOUT_DEFAULT = new VmNull(null);
 
   // worthwhile to create this lazily?

pkl-core/src/main/java/org/pkl/core/runtime/VmObject.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,42 +18,69 @@ package org.pkl.core.runtime;
 import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.frame.MaterializedFrame;
+import com.oracle.truffle.api.object.DynamicObject;
+import com.oracle.truffle.api.object.DynamicObjectLibrary;
+import com.oracle.truffle.api.object.Shape;
 import java.util.*;
 import java.util.function.BiFunction;
-import org.graalvm.collections.EconomicMap;
 import org.graalvm.collections.UnmodifiableEconomicMap;
 import org.pkl.core.ast.member.ObjectMember;
 import org.pkl.core.util.CollectionUtils;
+import org.pkl.core.util.DynamicObjectMapCursor;
 import org.pkl.core.util.EconomicMaps;
+import org.pkl.core.util.MapCursor;
 import org.pkl.core.util.Nullable;
 
-/** Corresponds to `pkl.base#Object`. */
+/**
-public abstract class VmObject extends VmObjectLike {
+ * Corresponds to `pkl.base#Object`.
+ *
+ * <p>Extends {@link DynamicObject} to leverage Truffle's object storage and inline caching
+ * capabilities. Cached property values are stored directly in this object using the Dynamic Object
+ * Model.
+ */
+public abstract class VmObject extends DynamicObject implements VmObjectLike {
+  // moved from VmObjectLike
+  protected final MaterializedFrame enclosingFrame;
+  protected @Nullable Object extraStorage;
+
   @CompilationFinal protected @Nullable VmObject parent;
   protected final UnmodifiableEconomicMap<Object, ObjectMember> members;
-  protected final EconomicMap<Object, Object> cachedValues;
 
   protected int cachedHash;
   private boolean forced;
 
-  public VmObject(
+  /**
-      MaterializedFrame enclosingFrame,
+   * Separate cache for local property values.
-      @Nullable VmObject parent,
+   *
-      UnmodifiableEconomicMap<Object, ObjectMember> members,
+   * <p>This is kept separate from the DynamicObject storage to avoid shape transitions.
-      EconomicMap<Object, Object> cachedValues) {
+   */
-    super(enclosingFrame);
+  private @Nullable IdentityHashMap<ObjectMember, Object> localPropertyCache;
-    this.parent = parent;
-    this.members = members;
-    this.cachedValues = cachedValues;
 
-    assert parent != this;
+  protected VmObject(
-  }
+      Shape shape,
-
-  public VmObject(
       MaterializedFrame enclosingFrame,
       @Nullable VmObject parent,
       UnmodifiableEconomicMap<Object, ObjectMember> members) {
-    this(enclosingFrame, parent, members, EconomicMaps.create());
+    super(shape);
+    this.enclosingFrame = enclosingFrame;
+    this.parent = parent;
+    this.members = members;
+    assert parent != this;
+  }
+
+  @Override
+  public final MaterializedFrame getEnclosingFrame() {
+    return enclosingFrame;
+  }
+
+  @Override
+  public final @Nullable Object getExtraStorage() {
+    return extraStorage;
+  }
+
+  @Override
+  public final void setExtraStorage(@Nullable Object extraStorage) {
+    this.extraStorage = extraStorage;
   }
 
   public final void lateInitParent(VmObject parent) {
@@ -67,11 +94,13 @@ public abstract class VmObject extends VmObjectLike {
   }
 
   @Override
+  @TruffleBoundary
   public final boolean hasMember(Object key) {
     return EconomicMaps.containsKey(members, key);
   }
 
   @Override
+  @TruffleBoundary
   public final @Nullable ObjectMember getMember(Object key) {
     return EconomicMaps.get(members, key);
   }
@@ -82,23 +111,81 @@ public abstract class VmObject extends VmObjectLike {
   }
 
   @Override
+  @TruffleBoundary
   public @Nullable Object getCachedValue(Object key) {
-    return EconomicMaps.get(cachedValues, key);
+    return DynamicObjectLibrary.getUncached().getOrDefault(this, key, null);
-  }
-
-  @Override
-  public final void setCachedValue(Object key, Object value) {
-    EconomicMaps.put(cachedValues, key, value);
-  }
-
-  @Override
-  public final boolean hasCachedValue(Object key) {
-    return EconomicMaps.containsKey(cachedValues, key);
   }
 
   @Override
   @TruffleBoundary
-  public final boolean iterateMemberValues(MemberValueConsumer consumer) {
+  public void setCachedValue(Object key, Object value) {
+    DynamicObjectLibrary.getUncached().put(this, key, value);
+  }
+
+  @Override
+  @TruffleBoundary
+  public boolean hasCachedValue(Object key) {
+    return DynamicObjectLibrary.getUncached().containsKey(this, key);
+  }
+
+  @Override
+  public MapCursor<Object, Object> getCachedValueEntries() {
+    return new DynamicObjectMapCursor(this);
+  }
+
+  @Override
+  @TruffleBoundary
+  public int getCachedValueCount() {
+    return DynamicObjectLibrary.getUncached().getKeyArray(this).length;
+  }
+
+  /**
+   * Clean all cached values. Local or otherwise. Resets cached values to null without removing the
+   * keys, preserving the object's shape for pre-allocated slots.
+   */
+  @TruffleBoundary
+  public void cleanAllCachedValues() {
+    if (localPropertyCache != null) {
+      localPropertyCache.clear();
+    }
+
+    var lib = DynamicObjectLibrary.getUncached();
+    Object[] keys = lib.getKeyArray(this);
+    for (Object key : keys) {
+      lib.put(this, key, null);
+    }
+
+    forced = false;
+  }
+
+  /**
+   * Gets a cached local property value.
+   *
+   * @param property the ObjectMember representing the local property declaration
+   * @return the cached value, or null if not cached
+   */
+  @TruffleBoundary
+  public @Nullable Object getLocalCachedValue(ObjectMember property) {
+    return localPropertyCache == null ? null : localPropertyCache.get(property);
+  }
+
+  /**
+   * Sets a cached local property value.
+   *
+   * @param property the ObjectMember representing the local property declaration
+   * @param value the value to cache
+   */
+  @TruffleBoundary
+  public void setLocalCachedValue(ObjectMember property, Object value) {
+    if (localPropertyCache == null) {
+      localPropertyCache = new IdentityHashMap<>(4);
+    }
+    localPropertyCache.put(property, value);
+  }
+
+  @Override
+  @TruffleBoundary
+  public final boolean iterateMemberValues(VmObjectLike.MemberValueConsumer consumer) {
     var visited = new HashSet<>();
     return iterateMembers(
         (key, member) -> {
@@ -112,14 +199,16 @@ public abstract class VmObject extends VmObjectLike {
 
   @Override
   @TruffleBoundary
-  public final boolean forceAndIterateMemberValues(ForcedMemberValueConsumer consumer) {
+  public final boolean forceAndIterateMemberValues(
+      VmObjectLike.ForcedMemberValueConsumer consumer) {
     force(false, false);
     return iterateAlreadyForcedMemberValues(consumer);
   }
 
   @Override
   @TruffleBoundary
-  public final boolean iterateAlreadyForcedMemberValues(ForcedMemberValueConsumer consumer) {
+  public final boolean iterateAlreadyForcedMemberValues(
+      VmObjectLike.ForcedMemberValueConsumer consumer) {
     var visited = new HashSet<>();
     return iterateMembers(
         (key, member) -> {
@@ -158,6 +247,9 @@ public abstract class VmObject extends VmObjectLike {
 
     if (recurse) forced = true;
 
+    // use cached call node from this object's class to avoid getUncached() overhead
+    var callNode = getVmClass().getCachedCallNode();
+
     try {
       for (VmObjectLike owner = this; owner != null; owner = owner.getParent()) {
         var cursor = EconomicMaps.getEntries(owner.getMembers());
@@ -174,7 +266,7 @@ public abstract class VmObject extends VmObjectLike {
           var memberValue = getCachedValue(memberKey);
           if (memberValue == null) {
             try {
-              memberValue = VmUtils.doReadMember(this, owner, memberKey, member);
+              memberValue = VmUtils.doReadMember(this, owner, memberKey, member, true, callNode);
             } catch (VmUndefinedValueException e) {
               if (!allowUndefinedValues) throw e;
               continue;
@@ -208,7 +300,7 @@ public abstract class VmObject extends VmObjectLike {
    */
   @TruffleBoundary
   protected final Map<String, Object> exportMembers() {
-    var result = CollectionUtils.<String, Object>newLinkedHashMap(EconomicMaps.size(cachedValues));
+    var result = CollectionUtils.<String, Object>newLinkedHashMap(getCachedValueCount());
 
     iterateMemberValues(
         (key, member, value) -> {

pkl-core/src/main/java/org/pkl/core/runtime/VmObjectLike.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,53 +15,39 @@
  */
 package org.pkl.core.runtime;
 
-import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.frame.MaterializedFrame;
 import java.util.function.BiFunction;
 import org.graalvm.collections.UnmodifiableEconomicMap;
 import org.pkl.core.ast.member.ObjectMember;
+import org.pkl.core.util.MapCursor;
 import org.pkl.core.util.Nullable;
 
 /**
  * Corresponds to `pkl.base#Object|pkl.base#Function`. The lexical scope is a chain of
  * `VmObjectLike` instances.
  */
-public abstract class VmObjectLike extends VmValue {
+public interface VmObjectLike extends VmValue {
   /** The frame that was active when this object was instantiated. * */
-  protected final MaterializedFrame enclosingFrame;
+  MaterializedFrame getEnclosingFrame();
 
-  protected @Nullable Object extraStorage;
+  @Nullable
+  Object getExtraStorage();
 
-  protected VmObjectLike(MaterializedFrame enclosingFrame) {
+  void setExtraStorage(@Nullable Object extraStorage);
-    this.enclosingFrame = enclosingFrame;
+
+  default boolean hasExtraStorage() {
+    return getExtraStorage() != null;
   }
 
-  public final MaterializedFrame getEnclosingFrame() {
+  default @Nullable Object getEnclosingReceiver() {
-    return enclosingFrame;
+    return VmUtils.getReceiverOrNull(getEnclosingFrame());
   }
 
-  public final @Nullable Object getEnclosingReceiver() {
+  default @Nullable VmObjectLike getEnclosingOwner() {
-    return VmUtils.getReceiverOrNull(enclosingFrame);
+    return VmUtils.getOwnerOrNull(getEnclosingFrame());
   }
 
-  public final @Nullable VmObjectLike getEnclosingOwner() {
+  default boolean isModuleObject() {
-    return VmUtils.getOwnerOrNull(enclosingFrame);
-  }
-
-  public final boolean hasExtraStorage() {
-    return extraStorage != null;
-  }
-
-  public Object getExtraStorage() {
-    assert extraStorage != null;
-    return extraStorage;
-  }
-
-  public final void setExtraStorage(@Nullable Object extraStorage) {
-    this.extraStorage = extraStorage;
-  }
-
-  public boolean isModuleObject() {
     return false;
   }
 
@@ -69,41 +55,45 @@ public abstract class VmObjectLike extends VmValue {
    * Returns the parent object in the prototype chain. For each concrete subclass X of VmObjectLike,
    * the exact return type of this method is `X|VmTyped`.
    */
-  public abstract @Nullable VmObjectLike getParent();
+  @Nullable
+  VmObjectLike getParent();
 
   /** Always prefer this method over `getMembers().containsKey(key)`. */
-  @TruffleBoundary
+  boolean hasMember(Object key);
-  public abstract boolean hasMember(Object key);
 
   /** Always prefer this method over `getMembers().get(key)`. */
-  @TruffleBoundary
+  @Nullable
-  public abstract @Nullable ObjectMember getMember(Object key);
+  ObjectMember getMember(Object key);
 
   /** Returns the declared members of this object. */
-  public abstract UnmodifiableEconomicMap<Object, ObjectMember> getMembers();
+  UnmodifiableEconomicMap<Object, ObjectMember> getMembers();
 
   /**
    * Reads from the properties cache for this object. The cache contains the values of all members
    * defined in this object or an ancestor thereof which have been requested with this object as the
    * receiver.
    */
-  @TruffleBoundary
+  @Nullable
-  public abstract @Nullable Object getCachedValue(Object key);
+  Object getCachedValue(Object key);
 
   /**
    * Writes to the properties cache for this object. The cache contains the values of all members
    * defined in this object or an ancestor thereof which have been requested with this object as the
    * receiver.
    */
-  @TruffleBoundary
+  void setCachedValue(Object key, Object value);
-  public abstract void setCachedValue(Object key, Object value);
 
   /**
    * Prefer this method over {@link #getCachedValue} if the value is not required. (There is no
    * point in calling this method to determine whether to call {@link #getCachedValue}.)
    */
-  @TruffleBoundary
+  boolean hasCachedValue(Object key);
-  public abstract boolean hasCachedValue(Object key);
+
+  /** Returns a cursor for iterating over all cached values in this object. */
+  MapCursor<Object, Object> getCachedValueEntries();
+
+  /** Returns the number of cached values in this object. */
+  int getCachedValueCount();
 
   /**
    * Iterates over member definitions and their values in order of their definition, from the top of
@@ -118,15 +108,15 @@ public abstract class VmObjectLike extends VmValue {
    * remaining members are not visited, and `false` is returned. Otherwise, all members are visited,
    * and `true` is returned.
    */
-  public abstract boolean iterateMemberValues(MemberValueConsumer consumer);
+  boolean iterateMemberValues(MemberValueConsumer consumer);
 
   /**
    * Same as {@link #iterateMemberValues} except that it first performs a shallow {@link #force}. As
    * a consequence, values passed to {@code consumer} are guaranteed to be non-null.
    */
-  public abstract boolean forceAndIterateMemberValues(ForcedMemberValueConsumer consumer);
+  boolean forceAndIterateMemberValues(ForcedMemberValueConsumer consumer);
 
-  public abstract boolean iterateAlreadyForcedMemberValues(ForcedMemberValueConsumer consumer);
+  boolean iterateAlreadyForcedMemberValues(ForcedMemberValueConsumer consumer);
 
   /**
    * Iterates over member definitions in order of their definition, from the top of the prototype
@@ -135,19 +125,20 @@ public abstract class VmObjectLike extends VmValue {
    * members are not visited, and `false` is returned. Otherwise, all members are visited, and
    * `true` is returned.
    */
-  public abstract boolean iterateMembers(BiFunction<Object, ObjectMember, Boolean> consumer);
+  boolean iterateMembers(BiFunction<Object, ObjectMember, Boolean> consumer);
 
   /** Forces shallow or recursive (deep) evaluation of this object. */
-  public abstract void force(boolean allowUndefinedValues, boolean recurse);
+  void force(boolean allowUndefinedValues, boolean recurse);
 
   /**
    * Exports this object to an external representation. Does not export local, hidden, or external
    * properties
    */
-  public abstract Object export();
+  @Override
+  Object export();
 
   @FunctionalInterface
-  public interface MemberValueConsumer {
+  interface MemberValueConsumer {
     /**
      * Returns true if {@link #iterateMemberValues} should continue calling this method for the
      * remaining members, and false otherwise.
@@ -156,7 +147,7 @@ public abstract class VmObjectLike extends VmValue {
   }
 
   @FunctionalInterface
-  public interface ForcedMemberValueConsumer {
+  interface ForcedMemberValueConsumer {
     /**
      * Returns true if {@link #forceAndIterateMemberValues} should continue calling this method for
      * the remaining members, and false otherwise.

pkl-core/src/main/java/org/pkl/core/runtime/VmPair.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,7 +23,7 @@ import org.pkl.core.Pair;
 import org.pkl.core.util.Nullable;
 
 @ValueType
-public final class VmPair extends VmValue implements Iterable<Object> {
+public final class VmPair implements VmValue, Iterable<Object> {
   private final Object first;
   private final Object second;
 

pkl-core/src/main/java/org/pkl/core/runtime/VmRegex.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,7 +23,7 @@ import org.pkl.core.ValueFormatter;
 import org.pkl.core.util.Nullable;
 
 @ValueType
-public final class VmRegex extends VmValue {
+public final class VmRegex implements VmValue {
   private final Pattern pattern;
 
   public VmRegex(Pattern pattern) {

pkl-core/src/main/java/org/pkl/core/runtime/VmTypeAlias.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,7 +36,7 @@ import org.pkl.core.ast.type.TypeNode.UnknownTypeNode;
 import org.pkl.core.util.LateInit;
 import org.pkl.core.util.Nullable;
 
-public final class VmTypeAlias extends VmValue {
+public final class VmTypeAlias implements VmValue {
   private final SourceSection sourceSection;
   private final SourceSection headerSection;
   private final SourceSection @Nullable [] docComment;

pkl-core/src/main/java/org/pkl/core/runtime/VmTyped.java

@@ -19,6 +19,9 @@ import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.frame.MaterializedFrame;
 import com.oracle.truffle.api.instrumentation.InstrumentableNode.WrapperNode;
+import com.oracle.truffle.api.object.DynamicObject;
+import com.oracle.truffle.api.object.DynamicObjectLibrary;
+import com.oracle.truffle.api.object.Shape;
 import org.graalvm.collections.EconomicMap;
 import org.graalvm.collections.UnmodifiableEconomicMap;
 import org.pkl.core.Composite;
@@ -34,14 +37,99 @@ import org.pkl.core.util.Nullable;
 public final class VmTyped extends VmObject {
   @CompilationFinal @LateInit private VmClass clazz;
 
+  /**
+   * Creates a new VmTyped with the class's instance shape.
+   *
+   * @param enclosingFrame the frame that was active when this object was instantiated
+   * @param parent the parent in the prototype chain, or null
+   * @param clazz the class of this object, or null if it will be late-initialized
+   * @param members the declared members of this object
+   */
   public VmTyped(
       MaterializedFrame enclosingFrame,
       @Nullable VmTyped parent,
       // null -> will be initialized using lateInitVmClass() later
       @Nullable VmClass clazz,
       UnmodifiableEconomicMap<Object, ObjectMember> members) {
-    super(enclosingFrame, parent, members);
+    this(enclosingFrame, parent, clazz, members, getShapeForClass(clazz));
+  }
+
+  /**
+   * Creates a new VmTyped with a custom shape.
+   *
+   * <p>This constructor is used when a specific shape is needed, such as when amending an object
+   * where the shape may differ from the class's base instance shape.
+   *
+   * @param enclosingFrame the frame that was active when this object was instantiated
+   * @param parent the parent in the prototype chain, or null
+   * @param clazz the class of this object, or null if it will be late-initialized
+   * @param members the declared members of this object
+   * @param shape the Truffle shape for this object's cached value storage
+   */
+  public VmTyped(
+      MaterializedFrame enclosingFrame,
+      @Nullable VmTyped parent,
+      @Nullable VmClass clazz,
+      UnmodifiableEconomicMap<Object, ObjectMember> members,
+      Shape shape) {
+    super(shape, enclosingFrame, parent, members);
     this.clazz = clazz;
+    // pre-allocate cache slots for all members to stabilize the shape
+    preallocateCacheSlots(members);
+  }
+
+  /**
+   * Pre-allocates cache slots for all members by putting null values. This creates shape
+   * transitions upfront so all instances share the same final shape.
+   */
+  private void preallocateCacheSlots(UnmodifiableEconomicMap<Object, ObjectMember> members) {
+    var library = DynamicObjectLibrary.getUncached();
+    var cursor = members.getEntries();
+    while (cursor.advance()) {
+      library.put(this, cursor.getKey(), null);
+    }
+  }
+
+  private static Shape getShapeForClass(@Nullable VmClass clazz) {
+    return clazz != null ? clazz.getInstanceShape() : PklShape.getRootShape();
+  }
+
+  /** Returns this object for cached value storage. */
+  public DynamicObject getCachedValuesStorage() {
+    return this;
+  }
+
+  /**
+   * Gets a cached value using the provided library for PE-optimized access.
+   *
+   * @param key the property key
+   * @param library the DynamicObjectLibrary to use (should be cached via @CachedLibrary)
+   * @return the cached value, or null if not present
+   */
+  public @Nullable Object getCachedValue(Object key, DynamicObjectLibrary library) {
+    return library.getOrDefault(this, key, null);
+  }
+
+  /**
+   * Sets a cached value using the provided library for PE-optimized access.
+   *
+   * @param key the property key
+   * @param value the value to cache
+   * @param library the DynamicObjectLibrary to use (should be cached via @CachedLibrary)
+   */
+  public void setCachedValue(Object key, Object value, DynamicObjectLibrary library) {
+    library.put(this, key, value);
+  }
+
+  /**
+   * Checks if a cached value exists using the provided library for PE-optimized access.
+   *
+   * @param key the property key
+   * @param library the DynamicObjectLibrary to use (should be cached via @CachedLibrary)
+   * @return true if a value is cached for this key
+   */
+  public boolean hasCachedValue(Object key, DynamicObjectLibrary library) {
+    return library.containsKey(this, key);
   }
 
   public void lateInitVmClass(VmClass clazz) {

pkl-core/src/main/java/org/pkl/core/runtime/VmValue.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,30 +17,30 @@ package org.pkl.core.runtime;
 
 import org.pkl.core.util.Nullable;
 
-public abstract class VmValue {
+public interface VmValue {
-  public abstract VmClass getVmClass();
+  VmClass getVmClass();
 
-  public VmTyped getPrototype() {
+  default VmTyped getPrototype() {
     return getVmClass().getPrototype();
   }
 
-  public boolean isPrototype() {
+  default boolean isPrototype() {
     return false;
   }
 
-  public boolean isDynamic() {
+  default boolean isDynamic() {
     return this instanceof VmDynamic;
   }
 
-  public boolean isListing() {
+  default boolean isListing() {
     return this instanceof VmListing;
   }
 
-  public boolean isMapping() {
+  default boolean isMapping() {
     return this instanceof VmMapping;
   }
 
-  public boolean isTyped() {
+  default boolean isTyped() {
     return this instanceof VmTyped;
   }
 
@@ -48,21 +48,21 @@ public abstract class VmValue {
    * Tells if this value is a {@link VmCollection}, {@link VmListing}, or {@link VmDynamic} with
    * {@link VmDynamic#hasElements() elements}.
    */
-  public boolean isSequence() {
+  default boolean isSequence() {
     return false;
   }
 
   /** Forces recursive (deep) evaluation of this value. */
-  public abstract void force(boolean allowUndefinedValues);
+  void force(boolean allowUndefinedValues);
 
-  public abstract Object export();
+  Object export();
 
-  public abstract void accept(VmValueVisitor visitor);
+  void accept(VmValueVisitor visitor);
 
-  public abstract <T> T accept(VmValueConverter<T> converter, Iterable<Object> path);
+  <T> T accept(VmValueConverter<T> converter, Iterable<Object> path);
 
   /** Forces recursive (deep) evaluation of the given value. */
-  public static void force(Object value, boolean allowUndefinedValues) {
+  static void force(Object value, boolean allowUndefinedValues) {
     if (value instanceof VmValue vmValue) {
       vmValue.force(allowUndefinedValues);
     }
@@ -72,7 +72,7 @@ public abstract class VmValue {
    * Used to export values other than object member values. Such values aren't `@Nullable` (but can
    * be `VmNull`).
    */
-  public static Object export(Object value) {
+  static Object export(Object value) {
     if (value instanceof VmValue vmValue) {
       return vmValue.export();
     }
@@ -80,14 +80,10 @@ public abstract class VmValue {
   }
 
   /** Used to export object member values. Such values are `null` if they haven't been forced. */
-  public static @Nullable Object exportNullable(@Nullable Object value) {
+  static @Nullable Object exportNullable(@Nullable Object value) {
     if (value instanceof VmValue vmValue) {
       return vmValue.export();
     }
     return value;
   }
-
-  /** Enables calling `vmValue.equals()` when not behind a Truffle boundary. */
-  @Override
-  public abstract boolean equals(Object obj);
 }

pkl-core/src/main/java/org/pkl/core/util/DynamicObjectMapCursor.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright © 2026 Apple Inc. and the Pkl project authors. All rights reserved.
+ *
+ * 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
+ *
+ *     https://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 org.pkl.core.util;
+
+import com.oracle.truffle.api.object.DynamicObject;
+import com.oracle.truffle.api.object.DynamicObjectLibrary;
+
+/**
+ * A {@link MapCursor} implementation that iterates over the properties of a {@link DynamicObject}.
+ *
+ * <p>This cursor provides allocation-free iteration over DynamicObject properties by caching the
+ * key array at construction time and accessing values on demand.
+ */
+public final class DynamicObjectMapCursor implements MapCursor<Object, Object> {
+  private final DynamicObject object;
+  private final DynamicObjectLibrary library;
+  private final Object[] keys;
+  private int index = -1;
+
+  /**
+   * Creates a cursor for iterating over the given DynamicObject's properties.
+   *
+   * @param object the DynamicObject to iterate over
+   */
+  public DynamicObjectMapCursor(DynamicObject object) {
+    this.object = object;
+    this.library = DynamicObjectLibrary.getUncached();
+    this.keys = library.getKeyArray(object);
+  }
+
+  @Override
+  public boolean advance() {
+    index++;
+    return index < keys.length;
+  }
+
+  @Override
+  public Object getKey() {
+    if (index < 0 || index >= keys.length) {
+      throw new IllegalStateException("Cursor not positioned on a valid entry");
+    }
+    return keys[index];
+  }
+
+  @Override
+  public Object getValue() {
+    if (index < 0 || index >= keys.length) {
+      throw new IllegalStateException("Cursor not positioned on a valid entry");
+    }
+    return library.getOrDefault(object, keys[index], null);
+  }
+}

pkl-core/src/main/java/org/pkl/core/util/EmptyMapCursor.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright © 2026 Apple Inc. and the Pkl project authors. All rights reserved.
+ *
+ * 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
+ *
+ *     https://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 org.pkl.core.util;
+
+/** A cursor that iterates over zero entries. */
+public final class EmptyMapCursor<K, V> implements MapCursor<K, V> {
+  private static final EmptyMapCursor<Object, Object> INSTANCE = new EmptyMapCursor<>();
+
+  private EmptyMapCursor() {}
+
+  /** Returns the singleton empty cursor instance. */
+  @SuppressWarnings("unchecked")
+  public static <K, V> MapCursor<K, V> instance() {
+    return (MapCursor<K, V>) INSTANCE;
+  }
+
+  @Override
+  public boolean advance() {
+    return false;
+  }
+
+  @Override
+  public K getKey() {
+    throw new IllegalStateException("Cannot get key from empty cursor");
+  }
+
+  @Override
+  public V getValue() {
+    throw new IllegalStateException("Cannot get value from empty cursor");
+  }
+}

pkl-core/src/main/java/org/pkl/core/util/MapCursor.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright © 2026 Apple Inc. and the Pkl project authors. All rights reserved.
+ *
+ * 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
+ *
+ *     https://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 org.pkl.core.util;
+
+/** A cursor for iterating over map entries without allocating Entry objects. */
+public interface MapCursor<K, V> {
+  /**
+   * Advances the cursor to the next entry.
+   *
+   * @return true if there is a next entry, false if iteration is complete
+   */
+  boolean advance();
+
+  /**
+   * Returns the key at the current cursor position.
+   *
+   * @throws IllegalStateException if called before {@link #advance()} or after it returns false
+   */
+  K getKey();
+
+  /**
+   * Returns the value at the current cursor position.
+   *
+   * @throws IllegalStateException if called before {@link #advance()} or after it returns false
+   */
+  V getValue();
+}