diff --git a/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgDiffViewer.java b/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgDiffViewer.java
new file mode 100644
index 0000000000..3be23f823e
--- /dev/null
+++ b/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgDiffViewer.java
@@ -0,0 +1,147 @@
+/**
+ * Copyright (c) 2010, Sebastian Sdorra
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of SCM-Manager; nor the names of its
+ *    contributors may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * http://bitbucket.org/sdorra/scm-manager
+ *
+ */
+
+
+
+package sonia.scm.repository;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import sonia.scm.util.AssertUtil;
+import sonia.scm.util.IOUtil;
+import sonia.scm.util.Util;
+
+//~--- JDK imports ------------------------------------------------------------
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public class HgDiffViewer implements DiffViewer
+{
+
+  /** the logger for HgDiffViewer */
+  private static final Logger logger =
+    LoggerFactory.getLogger(HgDiffViewer.class);
+
+  //~--- constructors ---------------------------------------------------------
+
+  /**
+   * Constructs ...
+   *
+   *
+   * @param handler
+   * @param repositoryDirectory
+   */
+  public HgDiffViewer(HgRepositoryHandler handler, File repositoryDirectory)
+  {
+    this.handler = handler;
+    this.repositoryDirectory = repositoryDirectory;
+  }
+
+  /**
+   * Constructs ...
+   *
+   *
+   * @param handler
+   * @param repository
+   */
+  public HgDiffViewer(HgRepositoryHandler handler, Repository repository)
+  {
+    this(handler, handler.getDirectory(repository));
+  }
+
+  //~--- get methods ----------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @param revision
+   * @param path
+   * @param output
+   *
+   * @throws IOException
+   * @throws RepositoryException
+   */
+  @Override
+  public void getDiff(String revision, String path, OutputStream output)
+          throws IOException, RepositoryException
+  {
+    AssertUtil.assertIsNotEmpty(revision);
+    AssertUtil.assertIsNotNull(output);
+
+    ProcessBuilder builder =
+      new ProcessBuilder(handler.getConfig().getHgBinary(), "diff", "-c",
+                         revision, Util.nonNull(path));
+
+    if (logger.isDebugEnabled())
+    {
+      StringBuilder msg = new StringBuilder();
+
+      for (String param : builder.command())
+      {
+        msg.append(param).append(" ");
+      }
+
+      logger.debug(msg.toString());
+    }
+
+    Process p = builder.directory(repositoryDirectory).start();
+    InputStream input = null;
+
+    try
+    {
+      input = p.getInputStream();
+      IOUtil.copy(input, output);
+    }
+    finally
+    {
+      IOUtil.close(input);
+    }
+  }
+
+  //~--- fields ---------------------------------------------------------------
+
+  /** Field description */
+  private HgRepositoryHandler handler;
+
+  /** Field description */
+  private File repositoryDirectory;
+}
diff --git a/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgRepositoryHandler.java b/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgRepositoryHandler.java
index df53ada293..8dcb29c448 100644
--- a/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgRepositoryHandler.java
+++ b/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgRepositoryHandler.java
@@ -249,6 +249,40 @@ public class HgRepositoryHandler
     return changesetViewer;
   }
 
+  /**
+   * Method description
+   *
+   *
+   * @param repository
+   *
+   * @return
+   *
+   * @throws RepositoryException
+   */
+  @Override
+  public DiffViewer getDiffViewer(Repository repository)
+          throws RepositoryException
+  {
+    DiffViewer diffViewer = null;
+
+    AssertUtil.assertIsNotNull(repository);
+
+    String type = repository.getType();
+
+    AssertUtil.assertIsNotEmpty(type);
+
+    if (TYPE_NAME.equals(type))
+    {
+      diffViewer = new HgDiffViewer(this, repository);
+    }
+    else
+    {
+      throw new IllegalArgumentException("mercurial repository is required");
+    }
+
+    return diffViewer;
+  }
+
   /**
    * Method description
    *