diff --git a/ci/default.nix b/ci/default.nix
index 64b89f0217d9..68721e4b35a1 100644
--- a/ci/default.nix
+++ b/ci/default.nix
@@ -52,6 +52,7 @@ let
     in
     {
       shell = treefmtEval.config.build.devShell;
+      pkg = treefmtEval.config.build.wrapper;
     };
 
 in
diff --git a/flake.nix b/flake.nix
index 83ae9decf803..3cac4f6dd566 100644
--- a/flake.nix
+++ b/flake.nix
@@ -133,6 +133,8 @@
           default = import ./shell.nix { inherit system; };
         });
 
+      formatter = forAllSystems (system: (import ./ci { inherit system; }).fmt.pkg);
+
       /**
         A nested structure of [packages](https://nix.dev/manual/nix/latest/glossary#package-attribute-set) and other values.