nix: Switch to pre-commit hooks

.gitignore

@@ -6,4 +6,6 @@ dist
 
 /assets/tailwind.css
 
-/.vscode/spellright.dict
+/.vscode/spellright.dict
+
+/.pre-commit-config.yaml

flake.nix

@@ -11,8 +11,8 @@
 
     rust-flake.url = "github:juspay/rust-flake";
     rust-flake.inputs.nixpkgs.follows = "nixpkgs";
-    treefmt-nix.url = "github:numtide/treefmt-nix";
-    treefmt-nix.inputs.nixpkgs.follows = "nixpkgs";
+    git-hooks.url = "github:cachix/git-hooks.nix";
+    git-hooks.flake = false;
     cachix-push.url = "github:juspay/cachix-push";
 
     # We cache these inputs locally, and then have Omnix reference the catched inputs.

justfile

@@ -4,11 +4,9 @@ mod doc
 default:
     @just --list
 
-# Auto-format the source tree
-fmt:
-    treefmt
-
-alias f := fmt
+# Run all pre-commit hooks on all files
+pca:
+    pre-commit run -a
 
 # Run omnix-cli locally
 watch *ARGS:

nix/modules/flake-parts/devshell.nix

@@ -11,7 +11,7 @@ in
       name = "omnix-devshell";
       meta.description = "Omnix development environment";
       inputsFrom = [
-        config.treefmt.build.devShell
+        config.pre-commit.devShell
         self'.devShells.rust
       ];
       inherit (config.rust-project.crates."omnix-cli".crane.args)

nix/modules/flake-parts/pre-commit.nix

@@ -0,0 +1,15 @@
+{ inputs, ... }:
+{
+  imports = [
+    (inputs.git-hooks + /flake-module.nix)
+  ];
+
+  perSystem = {
+    pre-commit.settings = {
+      hooks = {
+        nixpkgs-fmt.enable = true;
+        rustfmt.enable = true;
+      };
+    };
+  };
+}