Use nix shell to fetch dependencies and run both erlang and javascript tests

.github/workflows/test.yml

@@ -3,21 +3,27 @@ name: test
 on:
   push:
     branches:
-      - master
       - main
   pull_request:
 
 jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: erlef/setup-beam@v1
+      - uses: actions/checkout@v5
+      - uses: cachix/install-nix-action@v31
         with:
-          otp-version: "27.1.2"
-          gleam-version: "1.12.0"
-          rebar3-version: "3"
-          # elixir-version: "1"
-      - run: gleam deps download
-      - run: gleam test
-      - run: gleam format --check src test
+          nix_path: nixpkgs=channel:nixos-unstable
+          github_access_token: ${{ secrets.GITHUB_TOKEN }}
+      - name: download gleam dependencies
+        shell: 'nix develop -c bash -e {0}'
+        run: gleam deps download
+      - name: gleam test on erlang target
+        shell: 'nix develop -c bash -e {0}'
+        run: gleam test
+      - name: gleam test on nodejs target
+        shell: 'nix develop -c bash -e {0}'
+        run: gleam test -t javascript
+      - name: gleam check formatting
+        shell: 'nix develop -c bash -e {0}'
+        run: gleam format --check src test

flake.nix

@@ -0,0 +1,26 @@
+{
+  description = "casper";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+  };
+
+  outputs =
+    { nixpkgs, ... }:
+    let
+      supportedSystems = [
+        "aarch64-darwin"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "x86_64-linux"
+      ];
+
+      forAllSystems =
+        function: nixpkgs.lib.genAttrs supportedSystems (system: function nixpkgs.legacyPackages.${system});
+    in
+    {
+      devShells = forAllSystems (pkgs: {
+        default = pkgs.callPackage ./shell.nix { };
+      });
+    };
+}

shell.nix

@@ -0,0 +1,12 @@
+{ pkgs, ... }:
+pkgs.mkShell {
+  buildInputs = with pkgs; [
+    gleam
+    rebar3
+    erlang
+
+    nodePackages.nodejs
+
+    nixfmt-rfc-style
+  ];
+}