diff --git a/build/Aegisub/Aegisub.vcxproj b/build/Aegisub/Aegisub.vcxproj
index 1b543cae7..50127c391 100644
--- a/build/Aegisub/Aegisub.vcxproj
+++ b/build/Aegisub/Aegisub.vcxproj
@@ -30,11 +30,7 @@
 
   <!-- Update git_version.h -->
   <Target Name="UpdateVersion" BeforeTargets="ClCompile">
-    <ExecShellScript
-      Command="$(MSBuildThisFileDirectory)..\version.sh"
-      WorkingDirectory="$(AegisubSourceBase)"
-      Configuration="@(ExecShellScript)"
-      Arguments="." />
+    <GitVersion Root="$(AegisubSourceBase)" />
   </Target>
 
   <!-- Project References -->
diff --git a/build/BuildTasks/BuildTasks.csproj b/build/BuildTasks/BuildTasks.csproj
index 8c93c8f50..4e1cef4a0 100644
--- a/build/BuildTasks/BuildTasks.csproj
+++ b/build/BuildTasks/BuildTasks.csproj
@@ -37,6 +37,9 @@
     <Reference Include="ICSharpCode.SharpZipLib">
       <HintPath>..\..\.nuget\lib\SharpZipLib.0.86.0\lib\20\ICSharpCode.SharpZipLib.dll</HintPath>
     </Reference>
+    <Reference Include="LibGit2Sharp">
+      <HintPath>..\..\.nuget\lib\LibGit2Sharp.0.17.0.0\lib\net35\LibGit2Sharp.dll</HintPath>
+    </Reference>
     <Reference Include="Microsoft.Build" />
     <Reference Include="Microsoft.Build.Engine" />
     <Reference Include="Microsoft.Build.Framework" />
@@ -52,11 +55,11 @@
   <ItemGroup>
     <Compile Include="DownloadTgzFile.cs" />
     <Compile Include="ExecShellScript.cs" />
+    <Compile Include="GitVersion.cs" />
     <Compile Include="MsysPath.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="ShellWrapper.cs" />
     <Compile Include="TarballProject.cs" />
-    <Compile Include="UpdateFile.cs" />
     <Compile Include="Utils.cs" />
   </ItemGroup>
   <ItemGroup>
@@ -64,6 +67,14 @@
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$(SolutionDir)\.nuget\NuGet.targets" Condition="Exists('$(SolutionDir)\.nuget\NuGet.targets')" />
+  <PropertyGroup>
+    <PostBuildEvent>
+if not exist "$(TargetDir)NativeBinaries" md "$(TargetDir)NativeBinaries"
+if not exist "$(TargetDir)NativeBinaries\x86" md "$(TargetDir)NativeBinaries\x86"
+xcopy /s /y /d "$(SolutionDir).nuget\lib\LibGit2Sharp.0.17.0.0\lib\net35\NativeBinaries\x86\*.*" "$(TargetDir)NativeBinaries\x86"
+if not exist "$(TargetDir)NativeBinaries\amd64" md "$(TargetDir)NativeBinaries\amd64"
+xcopy /s /y /d "$(SolutionDir).nuget\lib\LibGit2Sharp.0.17.0.0\lib\net35\NativeBinaries\amd64\*.*" "$(TargetDir)NativeBinaries\amd64"</PostBuildEvent>
+  </PropertyGroup>
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">
diff --git a/build/BuildTasks/GitVersion.cs b/build/BuildTasks/GitVersion.cs
new file mode 100644
index 000000000..4820328c8
--- /dev/null
+++ b/build/BuildTasks/GitVersion.cs
@@ -0,0 +1,113 @@
+// Copyright (c) 2014, Thomas Goyne <plorkyeran@aegisub.org>
+//
+// Permission to use, copy, modify, and distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+// Aegisub Project http://www.aegisub.org/
+
+using LibGit2Sharp;
+using System;
+using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+
+namespace BuildTasks {
+    public class GitVersion : Microsoft.Build.Utilities.Task {
+        public string Root { get; set; }
+
+        private static ObjectId LastSVNCommit = new ObjectId("16cd907fe7482cb54a7374cd28b8501f138116be");
+        private const string versionHTemplate =
+@"#define BUILD_GIT_VERSION_NUMBER {0}
+#define BUILD_GIT_VERSION_STRING ""{1}""
+#define TAGGED_RELEASE {2}
+#define INSTALLER_VERSION ""{3}""
+";
+        private const string versionXmlTemplate =
+@"<?xml version=""1.0"" encoding=""utf-8""?>
+<Project ToolsVersion=""4.0"" xmlns=""http://schemas.microsoft.com/developer/msbuild/2003"">
+  <PropertyGroup>
+    <GitVersionNumber>{0}</GitVersionNumber>
+    <GitVersionString>{1}</GitVersionString>
+  </PropertyGroup>
+</Project>
+";
+
+        private string UniqueAbbreviation(Repository repo, string full) {
+            for (int len = 7; len < 40; ++len) {
+                try {
+                    repo.Lookup(full.Substring(0, len));
+                    return full.Substring(0, len);
+                }
+                catch (AmbiguousSpecificationException) {
+                    continue;
+                }
+            }
+            return full;
+        }
+
+        private void WriteIfChanged(string path, string template, params object[] args) {
+            var body = string.Format(template, args).Replace("\r\n", "\n");
+            try {
+                var oldBody = File.ReadAllText(path);
+                if (body != oldBody)
+                    File.WriteAllText(path, body);
+            }
+            catch (IOException) {
+                File.WriteAllText(path, body);
+            }
+        }
+
+        public override bool Execute() {
+            string versionHPath = Root + "build/git_version.h";
+            string versionXmlPath = Root + "build/git_version.xml";
+
+            if (!Directory.Exists(Root + ".git")) {
+                if (File.Exists(versionHPath)) {
+                    Log.LogMessage("Using cached version.h");
+                    return true;
+                }
+                Log.LogError("git repo not found and no cached git_version.h");
+                return false;
+            }
+
+            int commits = 6962; // Rev ID when we switched away from SVN
+            string installerVersion = "0.0.0";
+            string versionStr = null;
+            bool taggedRelease = false;
+            using (var repo = new Repository(Root + ".git")) {
+                commits += repo.Commits.TakeWhile(c => !c.Id.Equals(LastSVNCommit)).Count();
+
+                foreach (var tag in repo.Tags) {
+                    if (!tag.Target.Id.Equals(repo.Head.Tip.Id)) continue;
+
+                    taggedRelease = true;
+                    versionStr = tag.Name;
+                    if (versionStr.StartsWith("v")) versionStr = versionStr.Substring(1);
+                    if (Regex.Match(versionStr, @"(\d)\.(\d)\.(\d)").Success)
+                        installerVersion = versionStr;
+                    break;
+                }
+
+                if (versionStr == null) {
+                    string branch = repo.Head.Name ?? "(unnamed branch)";
+                    versionStr = string.Format("{0}-{1}-{2}", commits, branch,
+                        UniqueAbbreviation(repo, repo.Head.Tip.Sha.ToString()));
+                }
+            }
+
+            WriteIfChanged(versionHPath,  versionHTemplate, commits, versionStr, taggedRelease ? "1" : "0", installerVersion);
+            WriteIfChanged(versionXmlPath,  versionXmlTemplate, commits, versionStr);
+
+            return true;
+        }
+    }
+}
diff --git a/build/BuildTasks/UpdateFile.cs b/build/BuildTasks/UpdateFile.cs
deleted file mode 100644
index 82a083922..000000000
--- a/build/BuildTasks/UpdateFile.cs
+++ /dev/null
@@ -1,40 +0,0 @@
-// Copyright (c) 2014, Thomas Goyne <plorkyeran@aegisub.org>
-//
-// Permission to use, copy, modify, and distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
-// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
-// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-//
-// Aegisub Project http://www.aegisub.org/
-
-using Microsoft.Build.Utilities;
-using System;
-
-namespace BuildTasks {
-    public class UpdateFile : Task {
-        public string File { get; set; }
-        public string Find { get; set; }
-        public string Replacement { get; set; }
-
-        public override bool Execute() {
-            try {
-              this.Log.LogMessage("Replacing '{0}' with '{1}' in '{2}'",
-                  this.Find, this.Replacement, this.File);
-              var text = System.IO.File.ReadAllText(this.File).Replace(this.Find, this.Replacement);
-              System.IO.File.WriteAllText(this.File, text);
-              return true;
-            }
-            catch (Exception e) {
-                this.Log.LogErrorFromException(e);
-                return false;
-            }
-        }
-    }
-}
diff --git a/build/BuildTasks/Utils.cs b/build/BuildTasks/Utils.cs
index d69b52e2f..e7acc1b79 100644
--- a/build/BuildTasks/Utils.cs
+++ b/build/BuildTasks/Utils.cs
@@ -14,24 +14,10 @@
 //
 // Aegisub Project http://www.aegisub.org/
 
-using Microsoft.Build.Evaluation;
-using Microsoft.Build.Framework;
-using System.Collections.Generic;
-using System.Linq;
 using System.Text.RegularExpressions;
-using System.Xml;
 
 namespace BuildTasks {
     static class Utils {
-        static public Dictionary<string, string> ReadPropertyMap(IBuildEngine be) {
-            var reader = XmlReader.Create(be.ProjectFileOfTaskNode);
-            return new Project(reader).AllEvaluatedProperties
-                .Where(x => !x.IsEnvironmentProperty)
-                .Where(x => !x.IsGlobalProperty)
-                .Where(x => !x.IsReservedProperty)
-                .ToDictionary(x => x.Name, x => x.EvaluatedValue);
-        }
-
         /// Convert an absolute windows path to an msys path
         static public string MungePath(string path) {
             var match = Regex.Match(path, @"([A-Za-z]):\\(.*)");
diff --git a/build/BuildTasks/packages.config b/build/BuildTasks/packages.config
index 6caeef935..967d43b65 100644
--- a/build/BuildTasks/packages.config
+++ b/build/BuildTasks/packages.config
@@ -1,4 +1,5 @@
-<?xml version="1.0" encoding="utf-8"?>
-<packages>
-  <package id="SharpZipLib" version="0.86.0" targetFramework="net45" />
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="LibGit2Sharp" version="0.17.0.0" targetFramework="net45" />
+  <package id="SharpZipLib" version="0.86.0" targetFramework="net45" />
 </packages>
\ No newline at end of file
diff --git a/build/tasks.props b/build/tasks.props
index 06cda1f4b..66d01f5a1 100644
--- a/build/tasks.props
+++ b/build/tasks.props
@@ -25,6 +25,6 @@
 
   <UsingTask TaskName="ExecShellScript" AssemblyFile="$(AegisubBinaryDir)BuildTasks.dll" />
   <UsingTask TaskName="MsysPath" AssemblyFile="$(AegisubBinaryDir)BuildTasks.dll" />
-  <UsingTask TaskName="UpdateFile" AssemblyFile="$(AegisubBinaryDir)BuildTasks.dll" />
+  <UsingTask TaskName="GitVersion" AssemblyFile="$(AegisubBinaryDir)BuildTasks.dll" />
 </Project>