feat: Add nix dev shell

Author: octet-stream

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -13,7 +13,8 @@ coverage
 @type
 
 # tsimp cache
-.tsimp
+/.tsimp
+/.direnv
 
 /src/**/*.js
 /lib

.husky/pre-commit

@@ -1,2 +1,3 @@
 pnpm run staged
 pnpm run lint:types
+git update-index --again

.lintstagedrc.json

@@ -1,6 +1,4 @@
 {
-  "*.{ts,js,json,jsonc}": [
-    "pnpm biome format --write --no-errors-on-unmatched",
-    "pnpm biome lint --write --no-errors-on-unmatched"
-  ]
+  "*.{ts,js,json,jsonc}": "pnpm biome check --write --no-errors-on-unmatched",
+  "*.nix": "nixfmt"
 }

.vscode/settings.json

@@ -26,5 +26,10 @@
     "editor.codeActionsOnSave": {
       "quickfix.biome": "explicit"
     }
+  },
+
+  "[nix]": {
+    "editor.defaultFormatter": "jnoortheen.nix-ide",
+    "editor.formatOnSave": true
   }
 }

flake.lock

@@ -0,0 +1,20 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
+    systems.url = "github:nix-systems/default";
+  };
+
+  outputs =
+    { nixpkgs, systems, ... }:
+    {
+      devShells = nixpkgs.lib.genAttrs (import systems) (
+        system:
+        let
+          pkgs = import nixpkgs { inherit system; };
+        in
+        {
+          default = import ./shell.nix { inherit pkgs; };
+        }
+      );
+    };
+}

flake.nix

@@ -0,0 +1,12 @@
+{
+  pkgs ? import <nixpkgs> { },
+}:
+with pkgs;
+mkShell {
+  packages = [
+    nixd
+    nixfmt-rfc-style
+    nodejs_22
+    corepack_22
+  ];
+}