cachix: build without docs

pkgs/by-name/ca/cachix/package.nix

@@ -1,9 +1,13 @@
 {
   lib,
+  haskell,
   haskellPackages,
 }:
-(lib.getBin haskellPackages.cachix).overrideAttrs (old: {
-  meta = (old.meta or { }) // {
-    mainProgram = old.meta.mainProgram or "cachix";
-  };
-})
+let
+  inherit (haskell.lib) compose;
+in
+lib.pipe haskellPackages.cachix [
+  compose.justStaticExecutables
+  (compose.overrideCabal { mainProgram = "cachix"; })
+  lib.getBin
+]