added sha256 sig
diff --git a/appveyor.yml b/appveyor.yml
index 1983477..ae609df 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -93,6 +93,8 @@
           git archive --format=tar master -o zstd-src.tar &&
           ..\zstd -19 zstd-src.tar &&
           appveyor PushArtifact zstd-src.tar.zst &&
+          certUtil -hashfile zstd-src.tar.zst SHA256 > zstd-src.sig.sha256 &&
+          appveyor PushArtifact zstd-src.sig.sha256 &&
           cd ..\..\bin\ &&
           7z a -tzip -mx9 zstd-win-release-%PLATFORM%.zip * &&
           appveyor PushArtifact zstd-win-release-%PLATFORM%.zip