diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionCacheChecker.java b/src/main/java/com/google/devtools/build/lib/actions/ActionCacheChecker.java
index e765121..081e977 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionCacheChecker.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ActionCacheChecker.java
@@ -42,7 +42,6 @@
 import com.google.devtools.build.lib.skyframe.TreeArtifactValue;
 import com.google.devtools.build.lib.skyframe.TreeArtifactValue.ArchivedRepresentation;
 import com.google.devtools.build.lib.vfs.OutputPermissions;
-import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.io.FileNotFoundException;
 import java.io.IOException;
@@ -231,8 +230,8 @@
       }
     }
     for (Artifact artifact : actionInputs.toList()) {
-      mdMap.put(
-          artifact.getExecPathString(), getInputMetadataMaybe(inputMetadataProvider, artifact));
+      FileArtifactValue inputMetadata = getInputMetadataMaybe(inputMetadataProvider, artifact);
+      mdMap.put(artifact.getExecPathString(), inputMetadata);
     }
     return !Arrays.equals(MetadataDigestUtils.fromMetadata(mdMap), entry.getFileDigest());
   }
@@ -606,6 +605,7 @@
       actionCache.accountMiss(MissReason.UNCONDITIONAL_EXECUTION);
       return true;
     }
+
     if (entry == null) {
       reportNewAction(handler, action);
       actionCache.accountMiss(MissReason.NOT_CACHED);
@@ -657,7 +657,7 @@
       InputMetadataProvider inputMetadataProvider, Artifact artifact) throws IOException {
     FileArtifactValue metadata = inputMetadataProvider.getInputMetadata(artifact);
     return (metadata != null && artifact.isConstantMetadata())
-        ? ConstantMetadataValue.INSTANCE
+        ? FileArtifactValue.ConstantMetadataValue.INSTANCE
         : metadata;
   }
 
@@ -666,7 +666,7 @@
       throws IOException, InterruptedException {
     FileArtifactValue metadata = outputMetadataStore.getOutputMetadata(artifact);
     return (metadata != null && artifact.isConstantMetadata())
-        ? ConstantMetadataValue.INSTANCE
+        ? FileArtifactValue.ConstantMetadataValue.INSTANCE
         : metadata;
   }
 
@@ -992,44 +992,4 @@
     }
   }
 
-  private static final class ConstantMetadataValue extends FileArtifactValue
-      implements FileArtifactValue.Singleton {
-    static final ConstantMetadataValue INSTANCE = new ConstantMetadataValue();
-    // This needs to not be of length 0, so it is distinguishable from a missing digest when written
-    // into a Fingerprint.
-    private static final byte[] DIGEST = new byte[1];
-
-    private ConstantMetadataValue() {}
-
-    @Override
-    public FileStateType getType() {
-      return FileStateType.REGULAR_FILE;
-    }
-
-    @Override
-    public byte[] getDigest() {
-      return DIGEST;
-    }
-
-    @Override
-    public FileContentsProxy getContentsProxy() {
-      throw new UnsupportedOperationException();
-    }
-
-    @Override
-    public long getSize() {
-      return 0;
-    }
-
-    @Override
-    public long getModifiedTime() {
-      return -1;
-    }
-
-    @Override
-    public boolean wasModifiedSinceDigest(Path path) {
-      throw new UnsupportedOperationException(
-          "ConstantMetadataValue doesn't support wasModifiedSinceDigest " + path.toString());
-    }
-  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionMiddlemanEvent.java b/src/main/java/com/google/devtools/build/lib/actions/ActionMiddlemanEvent.java
deleted file mode 100644
index 767a30c..0000000
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionMiddlemanEvent.java
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2015 The Bazel 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
-//
-//    http://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 com.google.devtools.build.lib.actions;
-
-import com.google.common.base.Preconditions;
-import com.google.devtools.build.lib.events.ExtendedEventHandler.Postable;
-
-/**
- * This event is fired during the build, when a middleman action is executed. Middleman actions
- * don't usually do any computation but we need them in the critical path because they depend on
- * other actions.
- */
-public final class ActionMiddlemanEvent implements Postable {
-
-  private final Action action;
-  private final InputMetadataProvider inputMetadataProvider;
-  private final long nanoTimeStart;
-  private final long nanoTimeFinish;
-
-  /**
-   * Create an event for action that has been started.
-   *
-   * @param action the middleman action.
-   * @param inputMetadataProvider the metadata about the inputs of the action
-   * @param nanoTimeStart the time when the action was started. This allow us to record more
-   *     accurately the time spent by the middleman action, since even for middleman actions we
-   *     execute some.
-   */
-  public ActionMiddlemanEvent(
-      Action action,
-      InputMetadataProvider inputMetadataProvider,
-      long nanoTimeStart,
-      long nanoTimeFinish) {
-    Preconditions.checkArgument(action.getActionType().isMiddleman(),
-        "Only middleman actions should be passed: %s", action);
-    this.action = action;
-    this.inputMetadataProvider = inputMetadataProvider;
-    this.nanoTimeStart = nanoTimeStart;
-    this.nanoTimeFinish = nanoTimeFinish;
-  }
-
-  /**
-   * Returns the associated action.
-   */
-  public Action getAction() {
-    return action;
-  }
-
-  /** Returns the metadata of the inputs of the action. */
-  public InputMetadataProvider getInputMetadataProvider() {
-    return inputMetadataProvider;
-  }
-
-  public long getNanoTimeStart() {
-    return nanoTimeStart;
-  }
-
-  public long getNanoTimeFinish() {
-    return nanoTimeFinish;
-  }
-}
diff --git a/src/main/java/com/google/devtools/build/lib/actions/BUILD b/src/main/java/com/google/devtools/build/lib/actions/BUILD
index a0cb04a..050b6c4 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/actions/BUILD
@@ -58,7 +58,6 @@
         "ActionKeyContext.java",
         "ActionLogBufferPathGenerator.java",
         "ActionLookupValue.java",
-        "ActionMiddlemanEvent.java",
         "ActionOwner.java",
         "ActionProgressEvent.java",
         "ActionRegistry.java",
@@ -436,6 +435,7 @@
         ":file_metadata",
         ":runfiles_tree",
         "//src/main/java/com/google/devtools/build/lib/skyframe:tree_artifact_value",
+        "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/util:hash_codes",
         "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
         "//third_party:guava",
diff --git a/src/main/java/com/google/devtools/build/lib/actions/FileArtifactValue.java b/src/main/java/com/google/devtools/build/lib/actions/FileArtifactValue.java
index 774175e..704972c 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/FileArtifactValue.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/FileArtifactValue.java
@@ -972,4 +972,46 @@
       return "singleton marker artifact value (" + hashCode() + ")";
     }
   }
+
+  /** {@link FileArtifactValue} subclass for artifacts with constant metadata. A singleton. */
+  public static final class ConstantMetadataValue extends FileArtifactValue
+      implements FileArtifactValue.Singleton {
+    static final ConstantMetadataValue INSTANCE = new ConstantMetadataValue();
+    // This needs to not be of length 0, so it is distinguishable from a missing digest when written
+    // into a Fingerprint.
+    private static final byte[] DIGEST = new byte[1];
+
+    private ConstantMetadataValue() {}
+
+    @Override
+    public FileStateType getType() {
+      return FileStateType.REGULAR_FILE;
+    }
+
+    @Override
+    public byte[] getDigest() {
+      return DIGEST;
+    }
+
+    @Override
+    public FileContentsProxy getContentsProxy() {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public long getSize() {
+      return 0;
+    }
+
+    @Override
+    public long getModifiedTime() {
+      return -1;
+    }
+
+    @Override
+    public boolean wasModifiedSinceDigest(Path path) {
+      throw new UnsupportedOperationException(
+          "ConstantMetadataValue doesn't support wasModifiedSinceDigest " + path);
+    }
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/MiddlemanAction.java b/src/main/java/com/google/devtools/build/lib/actions/MiddlemanAction.java
index 6ca6e8d..94b3fd8 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/MiddlemanAction.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/MiddlemanAction.java
@@ -22,6 +22,8 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.util.Fingerprint;
+import com.google.devtools.build.lib.vfs.BulkDeleter;
+import com.google.devtools.build.lib.vfs.Path;
 import javax.annotation.Nullable;
 
 /**
@@ -53,7 +55,18 @@
 
   @Override
   public ActionResult execute(ActionExecutionContext actionExecutionContext) {
-    throw new IllegalStateException("MiddlemanAction should never be executed");
+    return ActionResult.EMPTY;
+  }
+
+  @Override
+  public void prepare(
+      Path execRoot,
+      ArtifactPathResolver pathResolver,
+      @Nullable BulkDeleter bulkDeleter,
+      boolean cleanupArchivedArtifacts) {
+    // Runfiles trees are created as a side effect of building the output manifest, not the runfiles
+    // tree artifact. This method is overridden so that depending on the runfiles middleman does not
+    // delete the runfiles tree that's on the file system that someone decided it must be there.
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/actions/MiddlemanType.java b/src/main/java/com/google/devtools/build/lib/actions/MiddlemanType.java
index c10146a..dca392b 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/MiddlemanType.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/MiddlemanType.java
@@ -13,7 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.actions;
 
-/** The action type. */
+/** Deprecated, slated to be removed. */
 public enum MiddlemanType {
 
   /** A normal action. */
@@ -27,6 +27,9 @@
   RUNFILES_MIDDLEMAN;
 
   public boolean isMiddleman() {
-    return this != NORMAL;
+    // This value is always false, which means that in theory, the MiddlemanType enum is not useful
+    // anymore. It's kept here to facilitate an easy rollback for the change that made the enum
+    // unnecessary should trouble arise.
+    return false;
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/RunfilesArtifactValue.java b/src/main/java/com/google/devtools/build/lib/actions/RunfilesArtifactValue.java
index a3e933d..30ae791 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/RunfilesArtifactValue.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/RunfilesArtifactValue.java
@@ -18,7 +18,9 @@
 
 import com.google.common.base.MoreObjects;
 import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.actions.FileArtifactValue.ConstantMetadataValue;
 import com.google.devtools.build.lib.skyframe.TreeArtifactValue;
+import com.google.devtools.build.lib.util.Fingerprint;
 import com.google.devtools.build.lib.util.HashCodes;
 import com.google.devtools.build.skyframe.SkyValue;
 
@@ -43,13 +45,11 @@
   private final ImmutableList<TreeArtifactValue> treeValues;
 
   public RunfilesArtifactValue(
-      FileArtifactValue metadata,
       RunfilesTree runfilesTree,
       ImmutableList<Artifact> files,
       ImmutableList<FileArtifactValue> fileValues,
       ImmutableList<Artifact> trees,
       ImmutableList<TreeArtifactValue> treeValues) {
-    this.metadata = checkNotNull(metadata);
     this.runfilesTree = checkNotNull(runfilesTree);
     this.files = checkNotNull(files);
     this.fileValues = checkNotNull(fileValues);
@@ -59,10 +59,41 @@
         files.size() == fileValues.size() && trees.size() == treeValues.size(),
         "Size mismatch: %s",
         this);
+
+    // Compute the digest of this runfiles tree by combining its layout and the digests of every
+    // artifact it references.
+    this.metadata = FileArtifactValue.createProxy(computeDigest());
+  }
+
+  private byte[] computeDigest() {
+    Fingerprint result = new Fingerprint();
+
+    result.addInt(runfilesTree.getMapping().size());
+    for (var entry : runfilesTree.getMapping().entrySet()) {
+      result.addPath(entry.getKey());
+      result.addBoolean(entry.getValue() != null);
+      if (entry.getValue() != null) {
+        result.addPath(entry.getValue().getExecPath());
+      }
+    }
+
+    result.addInt(files.size());
+    for (int i = 0; i < files.size(); i++) {
+      FileArtifactValue value =
+          files.get(i).isConstantMetadata() ? ConstantMetadataValue.INSTANCE : fileValues.get(i);
+      value.addTo(result);
+    }
+
+    result.addInt(trees.size());
+    for (int i = 0; i < trees.size(); i++) {
+      result.addBytes(treeValues.get(i).getDigest());
+    }
+
+    return result.digestAndReset();
   }
 
   public RunfilesArtifactValue withOverriddenRunfilesTree(RunfilesTree overrideTree) {
-    return new RunfilesArtifactValue(metadata, overrideTree, files, fileValues, trees, treeValues);
+    return new RunfilesArtifactValue(overrideTree, files, fileValues, trees, treeValues);
   }
 
   /** Returns the data of the artifact for this value, as computed by the action cache checker. */
diff --git a/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionProgressReceiver.java b/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionProgressReceiver.java
index a7684e7..cb6cc8c 100644
--- a/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionProgressReceiver.java
+++ b/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionProgressReceiver.java
@@ -19,7 +19,6 @@
 import com.google.devtools.build.lib.actions.Action;
 import com.google.devtools.build.lib.actions.ActionExecutionStatusReporter;
 import com.google.devtools.build.lib.actions.ActionLookupData;
-import com.google.devtools.build.lib.actions.MiddlemanType;
 import com.google.devtools.build.lib.analysis.ConfiguredTargetValue;
 import com.google.devtools.build.lib.skyframe.ActionExecutionInactivityWatchdog;
 import com.google.devtools.build.lib.skyframe.AspectCompletionValue;
@@ -184,7 +183,7 @@
   }
 
   private static boolean isActionReportWorthy(Action action) {
-    return action.getActionType() == MiddlemanType.NORMAL;
+    return !action.getActionType().isMiddleman();
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/metrics/criticalpath/CriticalPathComputer.java b/src/main/java/com/google/devtools/build/lib/metrics/criticalpath/CriticalPathComputer.java
index 6e5ad22..a6e6dff 100644
--- a/src/main/java/com/google/devtools/build/lib/metrics/criticalpath/CriticalPathComputer.java
+++ b/src/main/java/com/google/devtools/build/lib/metrics/criticalpath/CriticalPathComputer.java
@@ -26,7 +26,6 @@
 import com.google.devtools.build.lib.actions.ActionAnalysisMetadata;
 import com.google.devtools.build.lib.actions.ActionCompletionEvent;
 import com.google.devtools.build.lib.actions.ActionKeyContext;
-import com.google.devtools.build.lib.actions.ActionMiddlemanEvent;
 import com.google.devtools.build.lib.actions.ActionStartedEvent;
 import com.google.devtools.build.lib.actions.Actions;
 import com.google.devtools.build.lib.actions.AggregatedSpawnMetrics;
@@ -235,23 +234,6 @@
   }
 
   /**
-   * Record a middleman action execution. Even if middleman are almost instant, we record them
-   * because they depend on other actions and we need them for constructing the critical path.
-   *
-   * <p>For some rules with incorrect configuration transitions we might get notified several times
-   * for the same middleman. This should only happen if the actions are shared.
-   */
-  @Subscribe
-  @AllowConcurrentEvents
-  public void middlemanAction(ActionMiddlemanEvent event) throws InterruptedException {
-    Action action = event.getAction();
-    CriticalPathComponent component =
-        tryAddComponent(createComponent(action, event.getNanoTimeStart()));
-    finalizeActionStat(
-        event.getNanoTimeStart(), event.getNanoTimeFinish(), action, component, "middleman action");
-  }
-
-  /**
    * Try to add the component to the map of critical path components. If there is an existing
    * component for its primary output it uses that to update the rest of the outputs.
    *
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/ExecutionGraphModule.java b/src/main/java/com/google/devtools/build/lib/runtime/ExecutionGraphModule.java
index f931f4b..ea5cfcf 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/ExecutionGraphModule.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/ExecutionGraphModule.java
@@ -29,7 +29,6 @@
 import com.google.devtools.build.lib.actions.ActionCompletionEvent;
 import com.google.devtools.build.lib.actions.ActionExecutionMetadata;
 import com.google.devtools.build.lib.actions.ActionInput;
-import com.google.devtools.build.lib.actions.ActionMiddlemanEvent;
 import com.google.devtools.build.lib.actions.ActionOwner;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.actions.CachedActionEvent;
@@ -181,7 +180,6 @@
 
   private ActionDumpWriter writer;
   private CommandEnvironment env;
-  private ExecutionGraphOptions options;
   private NanosToMillisSinceEpochConverter nanosToMillis =
       BlazeClock.createNanosToMillisSinceEpochConverter();
   // Only relevant for Skymeld: there may be multiple events and we only count the first one.
@@ -200,11 +198,6 @@
   }
 
   @VisibleForTesting
-  void setOptions(ExecutionGraphOptions options) {
-    this.options = options;
-  }
-
-  @VisibleForTesting
   void setNanosToMillis(NanosToMillisSinceEpochConverter nanosToMillis) {
     this.nanosToMillis = nanosToMillis;
   }
@@ -234,7 +227,6 @@
                                 BuildReport.newBuilder().setCode(Code.BUILD_REPORT_WRITE_FAILED))
                             .build())));
       }
-      this.options = options;
     }
   }
 
@@ -329,24 +321,6 @@
         event.getNanoTimeFinish());
   }
 
-  /**
-   * Record a middleman action execution. We may not needs this since we expand the runfiles
-   * supplier inputs, but it's left here in case we need it.
-   *
-   * <p>TODO(vanja) remove this if it's not necessary.
-   */
-  @Subscribe
-  @AllowConcurrentEvents
-  public void middlemanAction(ActionMiddlemanEvent event) {
-    if (options.logMiddlemanActions) {
-      actionEvent(
-          event.getAction(),
-          event.getInputMetadataProvider(),
-          event.getNanoTimeStart(),
-          event.getNanoTimeFinish());
-    }
-  }
-
   private void actionEvent(
       Action action,
       InputMetadataProvider inputMetadataProvider,
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ArtifactFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/ArtifactFunction.java
index 9b12ffa..167023d 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ArtifactFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ArtifactFunction.java
@@ -191,8 +191,7 @@
             "Null middleman action? %s",
             artifactDependencies);
 
-    FileArtifactValue individualMetadata = actionValue.getExistingFileArtifactValue(artifact);
-    return createRunfilesArtifactValue(artifact, (MiddlemanAction) action, individualMetadata, env);
+    return createRunfilesArtifactValue(artifact, (MiddlemanAction) action, env);
   }
 
   private static void mkdirForTreeArtifact(
@@ -382,7 +381,6 @@
   private static RunfilesArtifactValue createRunfilesArtifactValue(
       Artifact artifact,
       MiddlemanAction action,
-      FileArtifactValue value,
       SkyFunction.Environment env)
       throws InterruptedException {
     ImmutableList<Artifact> inputs = action.getInputs().toList();
@@ -425,7 +423,6 @@
     }
 
     return new RunfilesArtifactValue(
-        value,
         action.getRunfilesTree(),
         files.build(),
         fileValues.build(),
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java
index 6429b00..2ae3f90 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java
@@ -43,7 +43,6 @@
 import com.google.devtools.build.lib.actions.ActionKeyContext;
 import com.google.devtools.build.lib.actions.ActionLogBufferPathGenerator;
 import com.google.devtools.build.lib.actions.ActionLookupData;
-import com.google.devtools.build.lib.actions.ActionMiddlemanEvent;
 import com.google.devtools.build.lib.actions.ActionOutputDirectoryHelper;
 import com.google.devtools.build.lib.actions.ActionOutputDirectoryHelper.CreateOutputDirectoryException;
 import com.google.devtools.build.lib.actions.ActionOwner;
@@ -688,13 +687,6 @@
 
       if (token == null) {
         boolean eventPosted = false;
-        // Notify BlazeRuntimeStatistics about the action middleman 'execution'.
-        if (action.getActionType().isMiddleman()) {
-          eventHandler.post(
-              new ActionMiddlemanEvent(
-                  action, inputMetadataProvider, actionStartTime, BlazeClock.nanoTime()));
-          eventPosted = true;
-        }
 
         if (action instanceof NotifyOnActionCacheHit notify) {
           ExtendedEventHandler contextEventHandler = selectEventHandler(action);