add nix stuff

default.nix

@@ -0,0 +1,21 @@
+{ pkgs ? import <nixpkgs> {} }:
+
+pkgs.stdenv.mkDerivation {
+  name = "pnpm-project";
+  src = ./.;
+
+  buildInputs = [
+    pkgs.nodejs
+    pkgs.nodePackages.pnpm
+  ];
+
+  buildPhase = ''
+    pnpm install
+    pnpm build
+  '';
+
+  installPhase = ''
+    mkdir -p $out
+    cp -r dist/* $out/
+  '';
+}

flake.nix

@@ -0,0 +1,24 @@
+{
+  description = "Flake for building pnpm project";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+      in {
+        defaultPackage = pkgs.callPackage ./default.nix {};
+
+        devShell = pkgs.mkShell {
+          buildInputs = [
+            pkgs.nodejs
+            pkgs.nodePackages.pnpm
+          ];
+        };
+      }
+    );
+}