diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionEnvironment.java b/src/main/java/com/google/devtools/build/lib/actions/ActionEnvironment.java
index d074c39..5524e29 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ActionEnvironment.java
@@ -16,6 +16,7 @@
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.util.Fingerprint;
 import java.util.Map;
 import java.util.Set;
@@ -26,15 +27,17 @@
  * Environment variables for build or test actions.
  *
  * <p>The action environment consists of two parts.
+ *
  * <ol>
  *   <li>All the environment variables with a fixed value, stored in a map.
  *   <li>All the environment variables inherited from the client environment, stored in a set.
  * </ol>
  *
- * <p>Inherited environment variables must be declared in the Action interface
- * (see {@link Action#getClientEnvironmentVariables}), so that the dependency on the client
- * environment is known to the execution framework for correct incremental builds.
+ * <p>Inherited environment variables must be declared in the Action interface (see {@link
+ * Action#getClientEnvironmentVariables}), so that the dependency on the client environment is known
+ * to the execution framework for correct incremental builds.
  */
+@AutoCodec
 public final class ActionEnvironment {
   /**
    * An empty environment, mainly for testing. Production code should never use this, but instead
@@ -63,15 +66,16 @@
         inheritedEnv.add(key);
       }
     }
-    return create(fixedEnv, inheritedEnv);
+    return create(ImmutableMap.copyOf(fixedEnv), ImmutableSet.copyOf(inheritedEnv));
   }
 
   private final ImmutableMap<String, String> fixedEnv;
   private final ImmutableSet<String> inheritedEnv;
 
-  private ActionEnvironment(Map<String, String> fixedEnv, Set<String> inheritedEnv) {
-    this.fixedEnv = ImmutableMap.copyOf(fixedEnv);
-    this.inheritedEnv = ImmutableSet.copyOf(inheritedEnv);
+  private ActionEnvironment(
+      ImmutableMap<String, String> fixedEnv, ImmutableSet<String> inheritedEnv) {
+    this.fixedEnv = fixedEnv;
+    this.inheritedEnv = inheritedEnv;
   }
 
   /**
@@ -79,7 +83,9 @@
    * undefined, so callers need to take care that the key set of the {@code fixedEnv} map and the
    * set of {@code inheritedEnv} elements are disjoint.
    */
-  public static ActionEnvironment create(Map<String, String> fixedEnv, Set<String> inheritedEnv) {
+  @AutoCodec.Instantiator
+  public static ActionEnvironment create(
+      ImmutableMap<String, String> fixedEnv, ImmutableSet<String> inheritedEnv) {
     if (fixedEnv.isEmpty() && inheritedEnv.isEmpty()) {
       return EMPTY;
     }
@@ -87,7 +93,7 @@
   }
 
   public static ActionEnvironment create(Map<String, String> fixedEnv) {
-    return new ActionEnvironment(fixedEnv, ImmutableSet.of());
+    return new ActionEnvironment(ImmutableMap.copyOf(fixedEnv), ImmutableSet.of());
   }
 
   public ImmutableMap<String, String> getFixedEnv() {
diff --git a/src/main/java/com/google/devtools/build/lib/actions/CompositeRunfilesSupplier.java b/src/main/java/com/google/devtools/build/lib/actions/CompositeRunfilesSupplier.java
index da119ab..750fcfe 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/CompositeRunfilesSupplier.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/CompositeRunfilesSupplier.java
@@ -18,6 +18,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Maps;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.io.IOException;
 import java.util.Map;
@@ -26,6 +27,7 @@
 // TODO(michajlo): Move creation to factory constructor and optimize structure of the returned
 // supplier, ie: [] -> EmptyRunfilesSupplier, [singleSupplier] -> supplier,
 // [Empty, single] -> single, and so on.
+@AutoCodec
 public class CompositeRunfilesSupplier implements RunfilesSupplier {
 
   private final ImmutableList<RunfilesSupplier> suppliers;
@@ -38,6 +40,7 @@
   /**
    * Create an instance combining all of {@code suppliers}, with earlier elements taking precedence.
    */
+  @AutoCodec.Instantiator
   public CompositeRunfilesSupplier(Iterable<RunfilesSupplier> suppliers) {
     this.suppliers = ImmutableList.copyOf(suppliers);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/EmptyRunfilesSupplier.java b/src/main/java/com/google/devtools/build/lib/actions/EmptyRunfilesSupplier.java
index 9cf6d1b..ddab7c9 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/EmptyRunfilesSupplier.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/EmptyRunfilesSupplier.java
@@ -17,10 +17,13 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec.Strategy;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Map;
 
 /** Empty implementation of RunfilesSupplier */
+@AutoCodec(strategy = Strategy.SINGLETON)
 public class EmptyRunfilesSupplier implements RunfilesSupplier {
 
   public static final EmptyRunfilesSupplier INSTANCE = new EmptyRunfilesSupplier();
diff --git a/src/main/java/com/google/devtools/build/lib/actions/ResourceSet.java b/src/main/java/com/google/devtools/build/lib/actions/ResourceSet.java
index 9668eba..3d1c749 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ResourceSet.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ResourceSet.java
@@ -16,19 +16,20 @@
 
 import com.google.common.base.Splitter;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.common.options.Converter;
 import com.google.devtools.common.options.OptionsParsingException;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 
 /**
- * Instances of this class represent an estimate of the resource consumption
- * for a particular Action, or the total available resources.  We plan to
- * use this to do smarter scheduling of actions, for example making sure
- * that we don't schedule jobs concurrently if they would use so much
- * memory as to cause the machine to thrash.
+ * Instances of this class represent an estimate of the resource consumption for a particular
+ * Action, or the total available resources. We plan to use this to do smarter scheduling of
+ * actions, for example making sure that we don't schedule jobs concurrently if they would use so
+ * much memory as to cause the machine to thrash.
  */
 @Immutable
+@AutoCodec
 public class ResourceSet {
 
   /** For actions that consume negligible resources. */
@@ -48,7 +49,7 @@
    * workstation.
    */
   private final double ioUsage;
-  
+
   private ResourceSet(double memoryMb, double cpuUsage, double ioUsage, int localTestCount) {
     this.memoryMb = memoryMb;
     this.cpuUsage = cpuUsage;
@@ -79,12 +80,13 @@
 
   /**
    * Returns a new ResourceSet with the provided values for memoryMb, cpuUsage, ioUsage, and
-   * localTestCount. Most action resource definitions should use
-   * {@link #createWithRamCpuIo(double, double, double)} or {@link #createWithLocalTestCount(int)}.
-   * Use this method primarily when constructing ResourceSets that represent available resources.
+   * localTestCount. Most action resource definitions should use {@link #createWithRamCpuIo(double,
+   * double, double)} or {@link #createWithLocalTestCount(int)}. Use this method primarily when
+   * constructing ResourceSets that represent available resources.
    */
-  public static ResourceSet create(double memoryMb, double cpuUsage, double ioUsage,
-      int localTestCount) {
+  @AutoCodec.Instantiator
+  public static ResourceSet create(
+      double memoryMb, double cpuUsage, double ioUsage, int localTestCount) {
     if (memoryMb == 0 && cpuUsage == 0 && ioUsage == 0 && localTestCount == 0) {
       return ZERO;
     }
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/RunfilesSupplierImpl.java b/src/main/java/com/google/devtools/build/lib/analysis/RunfilesSupplierImpl.java
index c609d3d..89c6741 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/RunfilesSupplierImpl.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/RunfilesSupplierImpl.java
@@ -21,6 +21,7 @@
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.actions.BaseSpawn;
 import com.google.devtools.build.lib.actions.RunfilesSupplier;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.io.IOException;
 import java.util.Map;
@@ -28,6 +29,7 @@
 
 /** {@link RunfilesSupplier} implementation wrapping a single {@link Runfiles} directory mapping. */
 // TODO(bazel-team): Consider renaming to SingleRunfilesSupplierImpl.
+@AutoCodec
 public class RunfilesSupplierImpl implements RunfilesSupplier {
   private final PathFragment runfilesDir;
   private final Runfiles runfiles;
@@ -60,10 +62,9 @@
    * @param runfiles the runfiles for runilesDir.
    * @param manifest runfiles' associated runfiles manifest artifact, if present.
    */
+  @AutoCodec.Instantiator
   public RunfilesSupplierImpl(
-      PathFragment runfilesDir,
-      Runfiles runfiles,
-      @Nullable Artifact manifest) {
+      PathFragment runfilesDir, Runfiles runfiles, @Nullable Artifact manifest) {
     Preconditions.checkArgument(!runfilesDir.isAbsolute());
     this.runfilesDir = Preconditions.checkNotNull(runfilesDir);
     this.runfiles = Preconditions.checkNotNull(runfiles);
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java b/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
index badf8ef..23005b7 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
@@ -60,6 +60,7 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetView;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.syntax.SkylarkList;
 import com.google.devtools.build.lib.util.Fingerprint;
 import com.google.devtools.build.lib.util.LazyString;
@@ -68,7 +69,6 @@
 import com.google.errorprone.annotations.CompileTimeConstant;
 import com.google.errorprone.annotations.FormatMethod;
 import com.google.errorprone.annotations.FormatString;
-import com.google.protobuf.GeneratedMessage.GeneratedExtension;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
@@ -79,22 +79,12 @@
 import javax.annotation.Nullable;
 
 /** An Action representing an arbitrary subprocess to be forked and exec'd. */
+@AutoCodec
 public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifier, CommandAction {
 
-
-  /** Sets extensions on ExtraActionInfo **/
-  protected static class ExtraActionInfoSupplier<T> {
-    private final GeneratedExtension<ExtraActionInfo, T> extension;
-    private final T value;
-
-    protected ExtraActionInfoSupplier(GeneratedExtension<ExtraActionInfo, T> extension, T value) {
-      this.extension = extension;
-      this.value = value;
-    }
-
-    void extend(ExtraActionInfo.Builder builder) {
-      builder.setExtension(extension, value);
-    }
+  /** Sets extensions on {@link ExtraActionInfo}. */
+  public interface ExtraActionInfoSupplier {
+    void extend(ExtraActionInfo.Builder builder);
   }
 
   private static final String GUID = "ebd6fce3-093e-45ee-adb6-bf513b602f0d";
@@ -109,7 +99,7 @@
   private final ResourceSet resourceSet;
   private final ImmutableMap<String, String> executionInfo;
 
-  private final ExtraActionInfoSupplier<?> extraActionInfoSupplier;
+  private final ExtraActionInfoSupplier extraActionInfoSupplier;
 
   /**
    * Constructs a SpawnAction using direct initialization arguments.
@@ -131,6 +121,7 @@
    * @param progressMessage the message printed during the progression of the build.
    * @param mnemonic the mnemonic that is reported in the master log.
    */
+  @AutoCodec.Instantiator
   public SpawnAction(
       ActionOwner owner,
       Iterable<Artifact> tools,
@@ -197,7 +188,7 @@
       RunfilesSupplier runfilesSupplier,
       String mnemonic,
       boolean executeUnconditionally,
-      ExtraActionInfoSupplier<?> extraActionInfoSupplier) {
+      ExtraActionInfoSupplier extraActionInfoSupplier) {
     super(owner, tools, inputs, runfilesSupplier, outputs, env);
     this.resourceSet = resourceSet;
     this.executionInfo = executionInfo;
@@ -611,7 +602,7 @@
 
     private CharSequence progressMessage;
     private String mnemonic = "Unknown";
-    protected ExtraActionInfoSupplier<?> extraActionInfoSupplier = null;
+    protected ExtraActionInfoSupplier extraActionInfoSupplier = null;
     private boolean disableSandboxing = false;
 
     /**
@@ -1346,9 +1337,8 @@
       return this;
     }
 
-    public <T> Builder setExtraActionInfo(
-        GeneratedExtension<ExtraActionInfo, T> extension, T value) {
-      this.extraActionInfoSupplier = new ExtraActionInfoSupplier<>(extension, value);
+    public <T> Builder setExtraActionInfo(ExtraActionInfoSupplier extraActionInfoSupplier) {
+      this.extraActionInfoSupplier = extraActionInfoSupplier;
       return this;
     }
 
@@ -1362,7 +1352,8 @@
    * Command line implementation that optimises for containing executable args, command lines, and
    * command lines spilled to param files.
    */
-  private static class SpawnActionCommandLine extends CommandLine {
+  @AutoCodec
+  static class SpawnActionCommandLine extends CommandLine {
     private final Object[] values;
 
     SpawnActionCommandLine(Object[] values) {