diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index b9e5ca1..6790e55 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -2,39 +2,24 @@ name: Nix CI
 
 on:
   push:
-    branches: [ main ]
+    branches: [main]
   pull_request:
-    branches: [ main ]
+    branches: [main]
 
 jobs:
-  configure:
-    runs-on: ubuntu-latest
-    outputs:
-      matrix: ${{ steps.set-matrix.outputs.matrix }}
-    steps:
-      - uses: actions/checkout@v4
-      - id: set-matrix
-        run: echo "matrix=$(nixci gh-matrix --systems=x86_64-linux,aarch64-darwin | jq -c .)" >> $GITHUB_OUTPUT
-
-  nix:
-    runs-on: ${{ matrix.system }}
-    permissions:
-      contents: read
-    needs: configure
+  tests:
+    runs-on: ${{ matrix.os }}
     strategy:
-      matrix: ${{ fromJson(needs.configure.outputs.matrix) }}
-      fail-fast: false
+      matrix:
+        os: [ubuntu-latest]
+        system: [x86_64-linux, aarch64-darwin]
     steps:
       - uses: actions/checkout@v4
+      - uses: cachix/install-nix-action@v25
+        with:
+          nix_path: nixpkgs=channel:nixos-unstable
+      - uses: DeterminateSystems/magic-nix-cache-action@v2
       - run: |
-          nixci \
+          nix build \
             --extra-access-tokens "github.com=${{ secrets.GITHUB_TOKEN }}" \
-            build \
-            --systems "${{ matrix.system }}" \
-            .#default.${{ matrix.subflake}}
-
-      - name: Upload artifact
-        uses: actions/upload-artifact@v3
-        with:
-          name: numscript-wasm-${{ matrix.system }}
-          path: build/numscript.wasm
\ No newline at end of file
+            .#default
diff --git a/flake.nix b/flake.nix
index 750575b..56a4c67 100644
--- a/flake.nix
+++ b/flake.nix
@@ -22,7 +22,7 @@
             (with darwin.apple_sdk.frameworks; [ CoreFoundation CoreServices ]);
 
       in with pkgs; {
-        devShells.default = mkShell {
+        packages.default = mkShell {
           name = "numscript-wasm";
           packages = inputs;