diff --git a/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java b/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java
index 04f7458..0b272fb 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java
@@ -19,6 +19,7 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.devtools.build.lib.actions.extra.ExtraActionInfo;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.collect.CollectionUtils;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
@@ -45,6 +46,7 @@
 import java.util.Collection;
 import java.util.Map;
 import java.util.Map.Entry;
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.GuardedBy;
 
 /**
@@ -600,4 +602,10 @@
   public SkylarkDict<String, String> getSkylarkSubstitutions() {
     return null;
   }
+
+  @Nullable
+  @Override
+  public PlatformInfo getExecutionPlatform() {
+    return null;
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java
index ec94b6c..57ad70d 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.actions;
 
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import javax.annotation.Nullable;
 
@@ -126,4 +127,11 @@
    */
   @ThreadSafe
   boolean discoversInputs();
+
+  /**
+   * Returns the {@link PlatformInfo} platform this action should be executed on. If the execution
+   * platform is {@code null}, then the host platform is assumed.
+   */
+  @Nullable
+  PlatformInfo getExecutionPlatform();
 }
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 9b8d8bc..608ea70 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/actions/BUILD
@@ -23,6 +23,7 @@
         "//src/main/java/com/google/devtools/build/lib:skylarkinterface",
         "//src/main/java/com/google/devtools/build/lib:unix",
         "//src/main/java/com/google/devtools/build/lib:util",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
         "//src/main/java/com/google/devtools/build/lib/buildeventstream",
         "//src/main/java/com/google/devtools/build/lib/buildeventstream/proto:build_event_stream_java_proto",
         "//src/main/java/com/google/devtools/build/lib/causes",
diff --git a/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java b/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java
index bc52055..437f4b1 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java
@@ -17,11 +17,13 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
 /** Base implementation of a Spawn. */
@@ -147,4 +149,10 @@
   public String getMnemonic() {
     return action.getMnemonic();
   }
+
+  @Override
+  @Nullable
+  public PlatformInfo getExecutionPlatform() {
+    return action.getExecutionPlatform();
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java b/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java
index fd548b6..eb09c6e 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java
@@ -16,7 +16,9 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import java.util.Collection;
+import javax.annotation.Nullable;
 
 /**
  * A delegating spawn that allow us to overwrite certain methods while maintaining the original
@@ -84,4 +86,10 @@
   public String getMnemonic() {
     return spawn.getMnemonic();
   }
+
+  @Override
+  @Nullable
+  public PlatformInfo getExecutionPlatform() {
+    return spawn.getExecutionPlatform();
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java b/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java
index 3857783..19cfedb 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java
@@ -17,6 +17,8 @@
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
 /**
@@ -135,4 +137,10 @@
   public String getMnemonic() {
     return owner.getMnemonic();
   }
+
+  @Override
+  @Nullable
+  public PlatformInfo getExecutionPlatform() {
+    return null;
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/Spawn.java b/src/main/java/com/google/devtools/build/lib/actions/Spawn.java
index 3a59d9f..7e51517 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/Spawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/Spawn.java
@@ -16,7 +16,9 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import java.util.Collection;
+import javax.annotation.Nullable;
 
 /**
  * An object representing a subprocess to be invoked, including its command and
@@ -107,4 +109,7 @@
    * Returns a mnemonic (string constant) for this kind of spawn.
    */
   String getMnemonic();
+
+  @Nullable
+  PlatformInfo getExecutionPlatform();
 }
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 74bd33a..7dd7312 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
@@ -55,6 +55,7 @@
 import com.google.devtools.build.lib.analysis.FilesToRunProvider;
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 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;
@@ -109,6 +110,8 @@
 
   private final ExtraActionInfoSupplier<?> extraActionInfoSupplier;
 
+  @Nullable private final PlatformInfo executionPlatform;
+
   /**
    * Constructs a SpawnAction using direct initialization arguments.
    *
@@ -154,6 +157,7 @@
         EmptyRunfilesSupplier.INSTANCE,
         mnemonic,
         false,
+        null,
         null);
   }
 
@@ -195,7 +199,8 @@
       RunfilesSupplier runfilesSupplier,
       String mnemonic,
       boolean executeUnconditionally,
-      ExtraActionInfoSupplier<?> extraActionInfoSupplier) {
+      ExtraActionInfoSupplier<?> extraActionInfoSupplier,
+      @Nullable PlatformInfo executionPlatform) {
     super(owner, tools, inputs, runfilesSupplier, outputs, env);
     this.resourceSet = resourceSet;
     this.executionInfo = executionInfo;
@@ -205,6 +210,7 @@
     this.mnemonic = mnemonic;
     this.executeUnconditionally = executeUnconditionally;
     this.extraActionInfoSupplier = extraActionInfoSupplier;
+    this.executionPlatform = executionPlatform;
   }
 
   @Override
@@ -460,6 +466,12 @@
     return actionExecutionContext.getSpawnActionContext(getMnemonic());
   }
 
+  @Override
+  @Nullable
+  public PlatformInfo getExecutionPlatform() {
+    return executionPlatform;
+  }
+
   /**
    * A spawn instance that is tied to a specific SpawnAction.
    */
@@ -611,6 +623,7 @@
     private String mnemonic = "Unknown";
     protected ExtraActionInfoSupplier<?> extraActionInfoSupplier = null;
     private boolean disableSandboxing = false;
+    @Nullable private PlatformInfo executionPlatform;
 
     /**
      * Creates a SpawnAction builder.
@@ -638,6 +651,7 @@
       this.commandLines = Lists.newArrayList(other.commandLines);
       this.progressMessage = other.progressMessage;
       this.mnemonic = other.mnemonic;
+      this.executionPlatform = other.executionPlatform;
     }
 
     /**
@@ -806,7 +820,8 @@
           progressMessage,
           new CompositeRunfilesSupplier(
               Iterables.concat(this.inputRunfilesSuppliers, this.toolRunfilesSuppliers)),
-          mnemonic);
+          mnemonic,
+          executionPlatform);
     }
 
     /**
@@ -837,7 +852,8 @@
         ImmutableMap<String, String> executionInfo,
         CharSequence progressMessage,
         RunfilesSupplier runfilesSupplier,
-        String mnemonic) {
+        String mnemonic,
+        PlatformInfo executionPlatform) {
       return new SpawnAction(
           owner,
           tools,
@@ -852,7 +868,8 @@
           runfilesSupplier,
           mnemonic,
           executeUnconditionally,
-          extraActionInfoSupplier);
+          extraActionInfoSupplier,
+          executionPlatform);
     }
 
     private ImmutableList<String> buildExecutableArgs(
@@ -1354,6 +1371,11 @@
       this.disableSandboxing = true;
       return this;
     }
+
+    public Builder setExecutionPlatform(@Nullable PlatformInfo executionPlatform) {
+      this.executionPlatform = executionPlatform;
+      return this;
+    }
   }
 
   /**
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java b/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java
index e29f0e5..6453482 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java
@@ -87,6 +87,7 @@
         new CompositeRunfilesSupplier(shadowedAction.getRunfilesSupplier(), runfilesSupplier),
         mnemonic,
         false,
+        null,
         null);
     this.shadowedAction = shadowedAction;
     this.createDummyOutput = createDummyOutput;
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java
index 70586b8..bb87356 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java
@@ -29,6 +29,7 @@
 import com.google.devtools.build.lib.actions.RunfilesSupplier;
 import com.google.devtools.build.lib.analysis.actions.CommandLine;
 import com.google.devtools.build.lib.analysis.actions.SpawnAction;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.util.Fingerprint;
 import com.google.devtools.build.lib.vfs.FileSystemUtils;
@@ -74,7 +75,8 @@
       Map<String, String> executionInfo,
       CharSequence progressMessage,
       RunfilesSupplier runfilesSupplier,
-      String mnemonic) {
+      String mnemonic,
+      @Nullable PlatformInfo executionPlatform) {
     super(
         owner,
         ImmutableList.<Artifact>of(),
@@ -89,7 +91,8 @@
         runfilesSupplier,
         mnemonic,
         false,
-        null);
+        null,
+        executionPlatform);
     mandatoryInputs = inputs;
     Preconditions.checkState(
         (bitcodeFiles == null) == (imports == null),
@@ -219,7 +222,8 @@
         ImmutableMap<String, String> executionInfo,
         CharSequence progressMessage,
         RunfilesSupplier runfilesSupplier,
-        String mnemonic) {
+        String mnemonic,
+        @Nullable PlatformInfo executionPlatform) {
       return new LtoBackendAction(
           inputsAndTools.toCollection(),
           bitcodeFiles,
@@ -232,7 +236,8 @@
           executionInfo,
           progressMessage,
           runfilesSupplier,
-          mnemonic);
+          mnemonic,
+          executionPlatform);
     }
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java
index 7cf2380..728c07c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java
@@ -64,6 +64,7 @@
         runfilesSupplier,
         "Genrule",
         false,
+        null,
         null);
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaCompileAction.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaCompileAction.java
index f9d6349..1dbd8b7 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaCompileAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaCompileAction.java
@@ -210,7 +210,8 @@
         runfiles,
         "Javac",
         false /*executeUnconditionally*/,
-        null /*extraActionInfoSupplier*/);
+        null /*extraActionInfoSupplier*/,
+        null /*executionPlatform*/);
     this.javaCompileCommandLine = javaCompileCommandLine;
     this.commandLine = commandLine;