diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
new file mode 100644
index 000000000..e4fc197ef
--- /dev/null
+++ b/.github/workflows/check.yml
@@ -0,0 +1,28 @@
+name: "Check & Cachix"
+on:
+  push:
+    branches:
+      - core
+      - trying
+      - staging
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2.3.4
+    - uses: cachix/install-nix-action@v13
+      with:
+        install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-2.4pre20210415_76980a1/install
+        extra_nix_config: |
+          experimental-features = nix-command flakes
+          system-features = nixos-test benchmark big-parallel kvm recursive-nix
+          substituters = https://nrdxp.cachix.org https://nix-community.cachix.org https://cache.nixos.org
+          trusted-public-keys = nrdxp.cachix.org-1:Fc5PSqY2Jm1TrWfm88l6cvGWwz3s93c6IOifQWnhNW4= nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs= cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=
+    - uses: cachix/cachix-action@v10
+      with:
+        name: nrdxp
+        signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
+        authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+    - run: nix -Lv flake check
+    - run: nix -Lv build ".#nixosConfigurations.NixOS.config.system.build.toplevel"
+    - run: nix -Lv develop -c echo OK