diff --git a/src/com/facebook/buck/cli/Main.java b/src/com/facebook/buck/cli/Main.java
index 5ea6588ce2f..230c29da4d1 100644
--- a/src/com/facebook/buck/cli/Main.java
+++ b/src/com/facebook/buck/cli/Main.java
@@ -45,6 +45,7 @@
 import com.facebook.buck.log.CommandThreadAssociation;
 import com.facebook.buck.log.LogConfig;
 import com.facebook.buck.log.Logger;
+import com.facebook.buck.model.BuckVersion;
 import com.facebook.buck.model.BuildId;
 import com.facebook.buck.parser.Parser;
 import com.facebook.buck.parser.ParserConfig;
@@ -567,6 +568,15 @@ public int runMainWithExitCode(
       if (!commandSemaphoreAcquired) {
         return BUSY_EXIT_CODE;
       }
+      Optional<String> currentVersion =
+          filesystem.readFileIfItExists(BuckConstant.CURRENT_VERSION_FILE);
+      if (!currentVersion.isPresent() || !currentVersion.get().equals(BuckVersion.getVersion())) {
+        filesystem.deleteRecursivelyIfExists(BuckConstant.ANNOTATION_PATH);
+        filesystem.deleteRecursivelyIfExists(BuckConstant.GEN_PATH);
+        filesystem.deleteRecursivelyIfExists(BuckConstant.SCRATCH_PATH);
+        filesystem.mkdirs(BuckConstant.CURRENT_VERSION_FILE.getParent());
+        filesystem.writeContentsToPath(BuckVersion.getVersion(), BuckConstant.CURRENT_VERSION_FILE);
+      }
     }
 
     PropertyFinder propertyFinder = new DefaultPropertyFinder(
diff --git a/src/com/facebook/buck/util/BuckConstant.java b/src/com/facebook/buck/util/BuckConstant.java
index 3c88dc2fec7..bde2d96eb19 100644
--- a/src/com/facebook/buck/util/BuckConstant.java
+++ b/src/com/facebook/buck/util/BuckConstant.java
@@ -30,6 +30,11 @@ public class BuckConstant {
    */
   public static final String BUCK_OUTPUT_DIRECTORY = "buck-out";
   public static final Path BUCK_OUTPUT_PATH = Paths.get("buck-out");
+  /**
+   * The version the buck output directory was created for
+   */
+  public static final Path CURRENT_VERSION_FILE =
+      BUCK_OUTPUT_PATH.resolve(".currentversion");
 
   // TODO(mbolin): The constants GEN_DIR, BIN_DIR, and ANNOTATION_DIR should be
   // package-private to the com.facebook.buck.rules directory. Currently, they are also used in the
diff --git a/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java b/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java
index 792619da807..78bb0e44218 100644
--- a/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java
+++ b/test/com/facebook/buck/testutil/integration/ProjectWorkspace.java
@@ -31,8 +31,10 @@
 import com.facebook.buck.io.ExecutableFinder;
 import com.facebook.buck.io.MoreFiles;
 import com.facebook.buck.io.MorePaths;
+import com.facebook.buck.model.BuckVersion;
 import com.facebook.buck.model.BuildId;
 import com.facebook.buck.testutil.TestConsole;
+import com.facebook.buck.util.BuckConstant;
 import com.facebook.buck.util.CapturingPrintStream;
 import com.facebook.buck.util.MoreStrings;
 import com.facebook.buck.util.ProcessExecutor;
@@ -43,21 +45,29 @@
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.eventbus.Subscribe;
 import com.martiansoftware.nailgun.NGContext;
 
 import org.junit.rules.TemporaryFolder;
 
+import java.io.BufferedOutputStream;
 import java.io.File;
 import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.channels.Channels;
+import java.nio.file.FileAlreadyExistsException;
 import java.nio.file.FileSystems;
 import java.nio.file.FileVisitResult;
 import java.nio.file.Files;
 import java.nio.file.InvalidPathException;
+import java.nio.file.NoSuchFileException;
+import java.nio.file.OpenOption;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.nio.file.SimpleFileVisitor;
 import java.nio.file.StandardCopyOption;
+import java.nio.file.StandardOpenOption;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.List;
 
@@ -135,10 +145,26 @@ public ProjectWorkspace(Path templateDir, TemporaryPaths temporaryFolder) {
    * This will copy the template directory, renaming files named {@code foo.fixture} to {@code foo}
    * in the process. Files whose names end in {@code .expected} will not be copied.
    */
+  @SuppressWarnings("PMD.EmptyCatchBlock")
   public ProjectWorkspace setUp() throws IOException {
 
     MoreFiles.copyRecursively(templatePath, destPath, BUILD_FILE_RENAME);
 
+    // Stamp the buck-out directory if it exists and isn't stamped already
+    try (OutputStream outputStream =
+             new BufferedOutputStream(
+                 Channels.newOutputStream(
+                     Files.newByteChannel(
+                         destPath.resolve(BuckConstant.CURRENT_VERSION_FILE),
+                         ImmutableSet.<OpenOption>of(
+                             StandardOpenOption.CREATE_NEW,
+                             StandardOpenOption.WRITE))))) {
+      outputStream.write(BuckVersion.getVersion().getBytes(Charsets.UTF_8));
+    } catch (FileAlreadyExistsException | NoSuchFileException e) {
+      // If the current version file already exists we don't need to create it
+      // If buck-out doesn't exist we don't need to stamp it
+    }
+
     // If there's a local.properties in the host project but not in the destination, make a copy.
     Path localProperties = FileSystems.getDefault().getPath("local.properties");
     Path destLocalProperties = destPath.resolve(localProperties.getFileName());