diff --git a/LibGit2Sharp.Tests/IndexerFixture.cs b/LibGit2Sharp.Tests/IndexerFixture.cs
new file mode 100644
index 000000000..73623faae
--- /dev/null
+++ b/LibGit2Sharp.Tests/IndexerFixture.cs
@@ -0,0 +1,51 @@
+using System;
+using System.IO;
+using LibGit2Sharp.Advanced;
+using LibGit2Sharp.Tests.TestHelpers;
+using Xunit;
+
+namespace LibGit2Sharp.Tests
+{
+    public class IndexerFixture : BaseFixture
+    {
+        [Fact]
+        public void CanIndexFromAFilePath()
+        {
+            TransferProgress copiedProgress = default(TransferProgress);
+            using (var repo = new Repository(SandboxStandardTestRepoGitDir()))
+            {
+                var expectedId = new ObjectId("a81e489679b7d3418f9ab594bda8ceb37dd4c695");
+                var path = Path.Combine(repo.Info.Path, "objects/pack/pack-a81e489679b7d3418f9ab594bda8ceb37dd4c695.pack");
+                TransferProgress progress;
+                var packId = Indexer.Index(out progress, path, repo.Info.WorkingDirectory, 438 /* 0666 */,
+                    onProgress: (p) => {
+                        copiedProgress = p;
+                        return true;
+                    });
+
+                Assert.Equal(expectedId, packId);
+                Assert.Equal(1628, progress.TotalObjects);
+                Assert.Equal(1628, copiedProgress.TotalObjects);
+            }
+        }
+
+        [Fact]
+        public void CanIndexFromAStream()
+        {
+            using (var repo = new Repository(SandboxStandardTestRepoGitDir()))
+            {
+                var expectedId = new ObjectId("a81e489679b7d3418f9ab594bda8ceb37dd4c695");
+                var path = Path.Combine(repo.Info.Path, "objects/pack/pack-a81e489679b7d3418f9ab594bda8ceb37dd4c695.pack");
+                TransferProgress progress;
+                using (var stream = new FileStream(path, FileMode.Open, FileAccess.Read))
+                {
+                    var packId = Indexer.Index(out progress, stream, repo.Info.WorkingDirectory, 438 /* 0666 */);
+                    Assert.Equal(expectedId, packId);
+                    Assert.Equal(1628, progress.TotalObjects);
+                }
+            }
+        }
+
+    }
+}
+
diff --git a/LibGit2Sharp.Tests/LibGit2Sharp.Tests.csproj b/LibGit2Sharp.Tests/LibGit2Sharp.Tests.csproj
index f93a24f30..6aafebda9 100644
--- a/LibGit2Sharp.Tests/LibGit2Sharp.Tests.csproj
+++ b/LibGit2Sharp.Tests/LibGit2Sharp.Tests.csproj
@@ -122,6 +122,7 @@
     <Compile Include="TreeDefinitionFixture.cs" />
     <Compile Include="TreeFixture.cs" />
     <Compile Include="UnstageFixture.cs" />
+    <Compile Include="IndexerFixture.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\LibGit2Sharp\LibGit2Sharp.csproj">
diff --git a/LibGit2Sharp/Advanced/Indexer.cs b/LibGit2Sharp/Advanced/Indexer.cs
new file mode 100644
index 000000000..efdfd32c0
--- /dev/null
+++ b/LibGit2Sharp/Advanced/Indexer.cs
@@ -0,0 +1,109 @@
+using System;
+using System.IO;
+using LibGit2Sharp.Core;
+using LibGit2Sharp.Handlers;
+using LibGit2Sharp.Core.Handles;
+
+namespace LibGit2Sharp.Advanced
+{
+    /// <summary>
+    /// The Indexer is our implementation of the git-index-pack command. It is used to process the packfile
+    /// which comes from the remote side on a fetch in order to create the corresponding .idx file.
+    /// </summary>
+    public class Indexer : IDisposable
+    {
+
+        readonly IndexerSafeHandle handle;
+        readonly TransferProgressHandler callback;
+
+        Indexer(string prefix, uint mode, ObjectDatabase odb = null, TransferProgressHandler onProgress = null)
+        {
+            /* The runtime won't let us pass null as a SafeHandle, wo create a "dummy" one to represent NULL */
+            ObjectDatabaseSafeHandle odbHandle = odb != null ? odb.Handle : new ObjectDatabaseSafeHandle();
+            callback = onProgress;
+            handle = Proxy.git_indexer_new(prefix, odbHandle, mode, GitDownloadTransferProgressHandler);
+        }
+
+        /// <summary>
+        /// Index the specified stream. This function runs synchronously; you may want to run it
+        /// in a background thread.
+        /// </summary>
+        /// <param name="progress">The amount of objects processed etc will be written to this structure on exit</param>
+        /// <param name="stream">Stream to run the indexing process on</param>
+        /// <param name="prefix">Path in which to store the pack and index files</param>
+        /// <param name="mode">Filemode to use for creating the pack and index files</param>
+        /// <param name="odb">Optional object db to use if the pack contains thin deltas</param>
+        /// <param name="onProgress">Function to call to report progress. It returns a boolean indicating whether
+        /// to continue working on the stream</param>
+        public static ObjectId Index(out TransferProgress progress, Stream stream, string prefix, uint mode, ObjectDatabase odb = null, TransferProgressHandler onProgress = null)
+        {
+            var buffer = new byte[65536];
+            int read;
+            var indexProgress = default(GitTransferProgress);
+
+            using (var idx = new Indexer(prefix, mode, odb, onProgress))
+            {
+                var handle = idx.handle;
+
+                do
+                {
+                    read = stream.Read(buffer, 0, buffer.Length);
+                    Proxy.git_indexer_append(handle, buffer, (UIntPtr)read, ref indexProgress);
+                } while (read > 0);
+
+                Proxy.git_indexer_commit(handle, ref indexProgress);
+
+                progress = new TransferProgress(indexProgress);
+                return Proxy.git_indexer_hash(handle);
+            }
+        }
+
+        /// <summary>
+        /// Index the packfile at the specified path. This function runs synchronously; you may want to run it
+        /// in a background thread.
+        /// <param name="progress">The amount of objects processed etc will be written to this structure on exit</param>
+        /// <param name="path">Path to the file to index</param>
+        /// <param name="prefix">Path in which to store the pack and index files</param>
+        /// <param name="mode">Filemode to use for creating the pack and index files</param>
+        /// <param name="odb">Optional object db to use if the pack contains thin deltas</param>
+        /// <param name="onProgress">Function to call to report progress. It returns a boolean indicating whether
+        /// to continue working on the stream</param>
+
+        /// </summary>
+        public static ObjectId Index(out TransferProgress progress, string path, string prefix, uint mode, ObjectDatabase odb = null, TransferProgressHandler onProgress = null)
+        {
+            using (var fs = new FileStream(path, FileMode.Open, FileAccess.Read))
+            {
+                return Index(out progress, fs, prefix, mode, odb, onProgress);
+            }
+        }
+
+        // This comes from RemoteCallbacks
+        /// <summary>
+        /// The delegate with the signature that matches the native git_transfer_progress_callback function's signature.
+        /// </summary>
+        /// <param name="progress"><see cref="GitTransferProgress"/> structure containing progress information.</param>
+        /// <param name="payload">Payload data.</param>
+        /// <returns>the result of the wrapped <see cref="TransferProgressHandler"/></returns>
+        int GitDownloadTransferProgressHandler(ref GitTransferProgress progress, IntPtr payload)
+        {
+            bool shouldContinue = true;
+
+            if (callback != null)
+            {
+                shouldContinue = callback(new TransferProgress(progress));
+            }
+
+            return Proxy.ConvertResultToCancelFlag(shouldContinue);
+        }
+
+        #region IDisposable implementation
+
+        public void Dispose()
+        {
+            handle.SafeDispose();
+        }
+
+        #endregion
+    }
+}
diff --git a/LibGit2Sharp/Core/Handles/IndexerSafeHandle.cs b/LibGit2Sharp/Core/Handles/IndexerSafeHandle.cs
new file mode 100644
index 000000000..1e60f6491
--- /dev/null
+++ b/LibGit2Sharp/Core/Handles/IndexerSafeHandle.cs
@@ -0,0 +1,13 @@
+using System;
+namespace LibGit2Sharp.Core.Handles
+{
+    internal class IndexerSafeHandle : SafeHandleBase
+    {
+        protected override bool ReleaseHandleImpl()
+        {
+            Proxy.git_indexer_free(handle);
+            return true;
+        }
+    }
+}
+
diff --git a/LibGit2Sharp/Core/NativeMethods.cs b/LibGit2Sharp/Core/NativeMethods.cs
index a8fb1eacf..0e84d56f7 100644
--- a/LibGit2Sharp/Core/NativeMethods.cs
+++ b/LibGit2Sharp/Core/NativeMethods.cs
@@ -1578,6 +1578,27 @@ internal static extern int git_treebuilder_insert(
 
         [DllImport(libgit2)]
         internal static extern int git_cherrypick(RepositorySafeHandle repo, GitObjectSafeHandle commit, GitCherryPickOptions options);
+
+        [DllImport(libgit2)]
+        public static extern int git_indexer_new(
+            out IndexerSafeHandle handle,
+            [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictFilePathMarshaler))] FilePath prefix,
+            uint mode,
+            ObjectDatabaseSafeHandle odbHandle,
+            git_transfer_progress_callback progress_callback,
+            IntPtr payload);
+
+        [DllImport(libgit2)]
+        public static extern int git_indexer_append(IndexerSafeHandle idx, byte[] data, UIntPtr size, ref GitTransferProgress progress);
+
+        [DllImport(libgit2)]
+        public static extern int git_indexer_commit(IndexerSafeHandle idx, ref GitTransferProgress progress);
+
+        [DllImport(libgit2)]
+        public static extern OidSafeHandle git_indexer_hash(IndexerSafeHandle idx);
+
+        [DllImport(libgit2)]
+        public static extern void git_indexer_free(IntPtr idx);
     }
 }
 // ReSharper restore InconsistentNaming
diff --git a/LibGit2Sharp/Core/Proxy.cs b/LibGit2Sharp/Core/Proxy.cs
index ab2f7eadc..04bc86fd4 100644
--- a/LibGit2Sharp/Core/Proxy.cs
+++ b/LibGit2Sharp/Core/Proxy.cs
@@ -1086,6 +1086,52 @@ public static void git_index_clear(Index index)
 
         #endregion
 
+        #region git_indexer_
+
+        public static IndexerSafeHandle git_indexer_new(FilePath prefix, ObjectDatabaseSafeHandle odbHandle, uint mode,
+                                                        NativeMethods.git_transfer_progress_callback progressCallback)
+        {
+            using (ThreadAffinity())
+            {
+                IndexerSafeHandle handle;
+
+                int res = NativeMethods.git_indexer_new(out handle, prefix, mode, odbHandle, progressCallback, IntPtr.Zero);
+                Ensure.ZeroResult(res);
+
+                return handle;
+            }
+        }
+
+        public static void git_indexer_append(IndexerSafeHandle handle, byte[] data, UIntPtr length, ref GitTransferProgress progress)
+        {
+            using (ThreadAffinity())
+            {
+                int res = NativeMethods.git_indexer_append(handle, data, length, ref progress);
+                Ensure.ZeroResult(res);
+            }
+        }
+
+        public static void git_indexer_commit(IndexerSafeHandle handle, ref GitTransferProgress progress)
+        {
+            using (ThreadAffinity())
+            {
+                int res = NativeMethods.git_indexer_commit(handle, ref progress);
+                Ensure.ZeroResult(res);
+            }
+        }
+
+        public static ObjectId git_indexer_hash(IndexerSafeHandle handle)
+        {
+            return NativeMethods.git_indexer_hash(handle).MarshalAsObjectId();
+        }
+
+        public static void git_indexer_free(IntPtr handle)
+        {
+            NativeMethods.git_indexer_free(handle);
+        }
+
+        #endregion
+
         #region git_merge_
 
         public static IndexSafeHandle git_merge_trees(RepositorySafeHandle repo, GitObjectSafeHandle ancestorTree, GitObjectSafeHandle ourTree, GitObjectSafeHandle theirTree)
diff --git a/LibGit2Sharp/LibGit2Sharp.csproj b/LibGit2Sharp/LibGit2Sharp.csproj
index 3ca4a3892..2aa011cf6 100644
--- a/LibGit2Sharp/LibGit2Sharp.csproj
+++ b/LibGit2Sharp/LibGit2Sharp.csproj
@@ -340,6 +340,8 @@
     <Compile Include="Core\RawContentStream.cs" />
     <Compile Include="Core\Handles\OdbStreamSafeHandle.cs" />
     <Compile Include="SupportedCredentialTypes.cs" />
+    <Compile Include="Core\Handles\IndexerSafeHandle.cs" />
+    <Compile Include="Advanced\Indexer.cs" />
   </ItemGroup>
   <ItemGroup>
     <CodeAnalysisDictionary Include="CustomDictionary.xml" />
diff --git a/LibGit2Sharp/ObjectDatabase.cs b/LibGit2Sharp/ObjectDatabase.cs
index b4b1da006..a0b77cd77 100644
--- a/LibGit2Sharp/ObjectDatabase.cs
+++ b/LibGit2Sharp/ObjectDatabase.cs
@@ -60,6 +60,11 @@ IEnumerator IEnumerable.GetEnumerator()
 
         #endregion
 
+        internal ObjectDatabaseSafeHandle Handle
+        {
+            get { return handle; }
+        }
+
         /// <summary>
         /// Determines if the given object can be found in the object database.
         /// </summary>
diff --git a/libgit2 b/libgit2
index 9bbc8f350..8acf058ff 160000
--- a/libgit2
+++ b/libgit2
@@ -1 +1 @@
-Subproject commit 9bbc8f350b80a5a6e94651ec667cf9e5d545b317
+Subproject commit 8acf058ff708582e9bbfe04e297d3b17a4d5c2e8