diff --git a/standalone/windows/build.sh b/standalone/windows/build.sh
index 230ffd2465..e0b72b4e5b 100644
--- a/standalone/windows/build.sh
+++ b/standalone/windows/build.sh
@@ -36,6 +36,8 @@ cd ..
 cabal install --only-dependencies -f"$FLAGS"
 
 runbuild () {
+	set -e
+
 	# Build git-annex
 	withcyg cabal configure -f"$FLAGS"
 	withcyg cabal build