refactor: Rewrote in golang.

flake.nix

@@ -2,19 +2,25 @@
   description = "Manage your .env files.";
 
   inputs = {
-    # nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
     nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
 
     flake-parts.url = "github:hercules-ci/flake-parts";
+    treefmt-nix.url = "github:numtide/treefmt-nix";
+    treefmt-nix.inputs.nixpkgs.follows = "nixpkgs";
   };
 
   outputs =
-    inputs@{ self
-    , flake-parts
+    inputs@{ flake-parts
     , nixpkgs
     , nixpkgs-unstable
+    , self
+    , treefmt-nix
     }:
     flake-parts.lib.mkFlake { inherit inputs; } {
+      imports = [
+        inputs.treefmt-nix.flakeModule
+      ];
       systems = [ "x86_64-linux" ];
 
       perSystem =
@@ -24,17 +30,67 @@
             config.allowUnfree = true;
 
             overlays = [
-              (final: prev: { unstable = inputs'.nixpkgs-unstable.legacyPackages; })
+              (_final: _prev: { unstable = inputs'.nixpkgs-unstable.legacyPackages; })
             ];
           };
 
+          treefmt = {
+            # Used to find the project root
+            projectRootFile = "flake.nix";
+            settings.global.excludes = [
+              ".direnv/**"
+              ".jj/**"
+              ".env"
+              ".envrc"
+              ".env.local"
+            ];
+
+
+            # Format nix files
+            programs.nixpkgs-fmt.enable = true;
+            # programs.deadnix.enable = true;
+
+            # Format go files
+            programs.goimports.enable = true;
+          };
+
+          packages.default = pkgs.buildGoModule rec {
+            pname = "envr";
+            version = "0.1.0";
+            src = ./.;
+            # If the build complains, uncomment this line
+            # vendorHash = "sha256:0000000000000000000000000000000000000000000000000000";
+            vendorHash = "sha256-aC82an6vYifewx4amfXLzk639jz9fF5bD5cF6krY0Ks=";
+            
+            nativeBuildInputs = [ pkgs.installShellFiles ];
+
+            ldflags = [
+              "-X github.com/sbrow/envr/cmd.version=v${version}"
+              # "-X github.com/sbrow/envr/cmd.commit=$(git rev-parse HEAD)"
+              # "-X github.com/sbrow/envr/cmd.date=$(date -u +%Y-%m-%dT%H:%M:%SZ)"
+            ];
+            
+            postBuild = ''
+              # Generate man pages
+              $GOPATH/bin/docgen -out ./man -format man
+            '';
+            
+            postInstall = ''
+              # Install man pages
+              installManPage ./man/*.1
+            '';
+          };
+
           devShells.default = pkgs.mkShell
             {
               buildInputs = with pkgs; [
-                age
                 fd
                 nushell
-                sqlite
+                go
+                gopls
+
+                gotools
+                cobra-cli
 
                 # IDE
                 unstable.helix