diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0260c286a..4d99b6516 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,6 +4,7 @@ on:
   push:
     branches:
     - master
+    - test-windows
   pull_request:
     branches:
     - master
@@ -20,11 +21,6 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: ubuntu-20.04
-            shell: bash
-            container: "{\"image\": \"elopeztob/alpine-haskell-stack-echidna:9.4.5\", \"options\": \"--user 1001\"}"
-          - os: macos-latest
-            shell: bash
           - os: windows-latest
             shell: msys2 {0}
 
@@ -96,6 +92,11 @@ jobs:
         env:
           HOST_OS: ${{ runner.os }}
 
+      - name: Install GMP in Stack MSYS2 (Windows)
+        if: runner.os == 'Windows'
+        run: |
+          stack exec -- pacman --noconfirm -S mingw-w64-x86_64-gmp
+
       - name: Build Dependencies
         run: |
           stack build --ghc-options="-Werror" --extra-include-dirs=$HOME/.local/include --extra-lib-dirs=$HOME/.local/lib --only-dependencies