diff --git a/appveyor.yml b/appveyor.yml
index c368e69..03b90a8 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -74,12 +74,9 @@ before_build:
 
 build_script:
  - echo packages:. > cabal.project
- - cabal %CABOPTS% build -j all
+ - cabal %CABOPTS% build -j1 all
  # Build from sdist if required.
- - ps: >-
-    If ($env:PKG_TEST -Match "yes") {
-       cabal sdist
-       echo "packages: dist-newstyle/sdist/*.tar.gz" | Out-File -Encoding ASCII cabal.project
-       cat cabal.project
-       cabal $env:CABOPTS build -j pkg:Win32
-    }
+ - cabal sdist
+ - "echo packages: dist-newstyle/sdist/*.tar.gz > cabal.project"
+ - type cabal.project
+ - cabal $env:CABOPTS build -j1 pkg:Win32