create a nix flake for a simple web application

Author: themarkness

flake.nix

@@ -0,0 +1,46 @@
+{
+  description = "A simple web application";
+
+  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
+      {
+        # Development environment
+        devShells.default = pkgs.mkShell {
+          buildInputs = with pkgs; [
+            nodejs_20
+            yarn
+          ];
+        };
+
+        # Build the application
+        packages.default = pkgs.stdenv.mkDerivation {
+          name = "my-web-app";
+          version = "1.0.0";
+          src = ./src;
+          
+          buildInputs = with pkgs; [
+            nodejs_20
+            yarn
+          ];
+
+          buildPhase = ''
+            yarn install
+            yarn build
+          '';
+
+          installPhase = ''
+            mkdir -p $out/bin
+            cp -r dist/* $out/bin/
+          '';
+        };
+      }
+    );
+}