try nix for ci

.github/workflows/test-nix.yml

@@ -0,0 +1,18 @@
+name: "Test Nix"
+on:
+  pull_request:
+  push:
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: cachix/install-nix-action@v18
+        with:
+          nix_path: nixpkgs = fetchTarball "https://github.com/NixOS/nixpkgs/tarball/nixos-23.05"
+      - uses: workflow/nix-shell-action@v3
+        with:
+          packages: nodejs_20,pandoc
+          script: |
+            node --version
+            pandoc --version

dev

@@ -0,0 +1,2 @@
+nix-shell --command return
+node --version

shell.nix

@@ -0,0 +1,10 @@
+let
+  nixpkgs = fetchTarball "https://github.com/NixOS/nixpkgs/tarball/nixos-23.05";
+  pkgs = import nixpkgs { config = {}; overlays = []; };
+in
+
+pkgs.mkShell {
+  packages = with pkgs; [
+    nodejs_20
+  ];
+}