diff --git a/appveyor.yml b/appveyor.yml
index 3ea123f9..050def78 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -29,7 +29,7 @@ build:
   project: src/Markdig.sln
   verbosity: minimal
 after_build:
-  - dotnet src/SpecFileGen -c Release --no-build
+  - dotnet run --project SpecFileGen/SpecFileGen.csproj -c Release
 before_package:
 - cmd: >-
      msbuild /t:pack /p:VersionSuffix="%MARKDIG_VERSION_SUFFIX%" /p:Configuration=Release Markdig/Markdig.csproj
diff --git a/src/SpecFileGen/Program.cs b/src/SpecFileGen/Program.cs
index 6249e9eb..bb8a1281 100644
--- a/src/SpecFileGen/Program.cs
+++ b/src/SpecFileGen/Program.cs
@@ -7,7 +7,11 @@ namespace SpecFileGen
 {
     class Program
     {
-        const string SpecificationsDirectory = "../../../../Markdig.Tests/Specs/";
+        static readonly string SpecificationsDirectory =
+            Path.GetFullPath(
+                Path.Combine(
+                    Path.GetDirectoryName(typeof(Spec).Assembly.Location),
+                    "../../../../Markdig.Tests/Specs/"));
 
         class Spec
         {