diff --git a/appveyor.yml b/appveyor.yml
index 8938394..016a9ee 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,19 +1,16 @@
 version: 0.0.{build}
 image: Visual Studio 2017
 
-install:
-  - choco install gitversion.portable -pre -y
 
 before_build:
   - cmd: dotnet --version
-  - ps: c:\ProgramData\chocolatey\lib\gitversion.portable\tools\gitversion.exe /l console /output buildserver
 
 build_script:
   - cmd: build.cmd
   - cmd: tests\CodeCoverage\CodeCoverage.cmd
 
 after_build:
-  - cmd: appveyor PushArtifact "artifacts\SixLabors.Core.%GitVersion_NuGetVersion%.nupkg"
+  - cmd: appveyor PushArtifact "artifacts\SixLabors.Core.%APPVEYOR_BUILD_VERSION%.nupkg"
 
 deploy:
   - provider: NuGet
@@ -24,14 +21,6 @@ deploy:
     artifact: /.*\.nupkg/
     on:
       branch: master
-  - provider: NuGet
-    server: https://www.myget.org/F/sixlabors-unstable/api/v2/package
-    symbol_server: https://www.myget.org/F/sixlabors-unstable/symbols/api/v2/package
-    api_key:
-      secure: V/lEHP0UeMWIpWd0fiNlY2IgbCnJKQlGdRksECdJbOBdaE20Fl0RNL7WyqHe02o4
-    artifact: /.*\.nupkg/
-    on:
-      branch: develop
 
 # prevent the double build when a branch has an active PR
 skip_branch_with_pr: true
diff --git a/build.cmd b/build.cmd
index e55aad0..6372b41 100644
--- a/build.cmd
+++ b/build.cmd
@@ -1,27 +1,6 @@
 @echo Off
 
-if not "%GitVersion_NuGetVersion%" == "" (
-    dotnet restore /p:packageversion=%GitVersion_NuGetVersion%
-)ELSE (
-    dotnet restore
-)
-
-ECHO Building nuget packages
-if not "%GitVersion_NuGetVersion%" == "" (
-    dotnet build -c Release /p:packageversion=%GitVersion_NuGetVersion%
-)ELSE (
-    dotnet build -c Release
-)
-if not "%errorlevel%"=="0" goto failure
-
-dotnet test ./tests/SixLabors.Core.Tests/SixLabors.Core.Tests.csproj
-
-
-if not "%GitVersion_NuGetVersion%" == "" (
-    dotnet pack ./src/SixLabors.Core/ -c Release --output ../../artifacts --no-build /p:packageversion=%GitVersion_NuGetVersion%
-)ELSE (
-    dotnet pack ./src/SixLabors.Core/ -c Release --output ../../artifacts --no-build
-)
+PowerShell -NoProfile -ExecutionPolicy Bypass -Command "& '.\build.ps1'"
 
 if not "%errorlevel%"=="0" goto failure
 
diff --git a/build.ps1 b/build.ps1
new file mode 100644
index 0000000..fcd63ae
--- /dev/null
+++ b/build.ps1
@@ -0,0 +1,110 @@
+
+# lets calulat the correct version here
+$fallbackVersion = "1.0.0";
+$version = ''
+
+$tagRegex = '^v?(\d+\.\d+\.\d+)(-([a-zA-Z]+)\.?(\d*))?$'
+
+# we are running on the build server 
+$isVersionTag = $env:APPVEYOR_REPO_TAG_NAME -match $tagRegex
+
+ if($isVersionTag){
+     
+    Write-Debug "Building commit tagged with a compatable version number"
+    
+    $version = $matches[1]
+     $postTag = $matches[3]
+     $count = $matches[4]
+     Write-Debug "version number: ${version} post tag: ${postTag} count: ${count}"
+     if("$postTag" -ne ""){
+        $version = "${version}-${postTag}"
+     }
+     if("$count" -ne ""){
+        # for consistancy with previous releases we pad the counter to only 4 places
+        $padded = $count.Trim().Trim('0').PadLeft(4,"0");
+        Write-Debug "count '$count', padded '${padded}'"
+
+        $version = "${version}${padded}"
+     }
+ }else {
+     
+    Write-Debug "Untagged"
+    $lastTag =  (git tag --list  --sort=-taggerdate)  | Out-String
+    $list = $lastTag.Split("`n")
+    foreach ($tag in $list) { 
+        
+    Write-Debug "testing ${tag}"
+        $tag = $tag.Trim();
+        if($tag -match $tagRegex){
+            Write-Debug "matched ${tag}"
+            $version = $matches[1];
+            break;
+        }
+    }
+    
+    if("$version" -eq ""){ 
+        $version = $fallbackVersion 
+        Write-Debug  "Failed to discover base version Fallback to '${version}'"
+    }else{
+        
+        Write-Debug  "Discovered base version from tags '${version}'"
+    }
+
+    $buildNumber = $env:APPVEYOR_BUILD_NUMBER
+
+    # build number replacement is padded to 6 places
+    $buildNumber = "$buildNumber".Trim().Trim('0').PadLeft(6,"0");
+    if("$env:APPVEYOR_PULL_REQUEST_NUMBER" -ne ""){
+        Write-Debug "building a PR"
+        
+        $prNumber = "$env:APPVEYOR_PULL_REQUEST_NUMBER".Trim().Trim('0').PadLeft(5,"0");
+        # this is a PR
+        $version = "${version}-PullRequest${prNumber}${buildNumber}";
+    }else{
+        Write-Debug "building a branch commit"
+
+        # this is a general branch commit
+        $branch = $env:APPVEYOR_REPO_BRANCH
+        
+        if("$branch" -eq ""){
+            $branch = ((git rev-parse --abbrev-ref HEAD) | Out-String).Trim()
+            
+            if("$branch" -eq ""){
+                $branch = "unknown"
+            }
+        }
+
+        $branch = $branch.Replace("/","-").ToLower()
+
+        if($branch.ToLower() -eq "master"){
+            $branch = "dev"
+        }
+        
+        $version = "${version}-${branch}${buildNumber}";
+    }
+ }
+
+if("$env:APPVEYOR_API_URL" -ne ""){
+    # update appveyor build number for this build
+    Invoke-RestMethod -Method "PUT" `
+                      -Uri "${env:APPVEYOR_API_URL}api/build" `
+                      -Body "{version:'${version}'}" `
+                      -ContentType "application/json"
+}
+
+Write-Host "Building version '${version}'"
+dotnet restore /p:packageversion=$version
+
+Write-Host "Building projects"
+dotnet build -c Release /p:packageversion=$version
+
+if ($LASTEXITCODE ){ Exit $LASTEXITCODE }
+
+if ( $env:CI -ne "True") {
+    dotnet test ./tests/SixLabors.Core.Tests/SixLabors.Core.Tests.csproj --no-build -c Release
+}
+if ($LASTEXITCODE ){ Exit $LASTEXITCODE }
+
+Write-Host "Packaging projects"
+dotnet pack ./src/SixLabors.Core/ -c Release --output ../../artifacts --no-build  /p:packageversion=$version
+if ($LASTEXITCODE ){ Exit $LASTEXITCODE }
\ No newline at end of file