{ description = "A Nix-flake-based Java development environment"; inputs.nixpkgs.url = "https://flakehub.com/f/NixOS/nixpkgs/0.1.*.tar.gz"; outputs = { self, nixpkgs }: let javaVersion = 20; # Change this value to update the whole stack overlays = [ (final: prev: rec { jdk = prev."jdk${toString javaVersion}"; gradle = prev.gradle.override { java = jdk; }; maven = prev.maven.override { inherit jdk; }; }) ]; supportedSystems = [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ]; forEachSupportedSystem = f: nixpkgs.lib.genAttrs supportedSystems (system: f { pkgs = import nixpkgs { inherit overlays system; }; }); in { devShells = forEachSupportedSystem ({ pkgs }: { default = pkgs.mkShell { packages = with pkgs; [ gradle jdk maven jdt-language-server ]; }; }); }; }