Add 'users/glittershark/xanthous/' from commit '53b56744f4'

git-subtree-dir: users/glittershark/xanthous
git-subtree-mainline: 91f53f02d8
git-subtree-split: 53b56744f4

users/glittershark/xanthous/.github/workflows/haskell.yml

@@ -0,0 +1,15 @@
+name: Haskell CI
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: Nix Build
+      with:
+        args: default.nix --arg failOnWarnings true
+      uses: ./.github/actions/nix-build