fix tests }:3

flake.nix

@@ -16,11 +16,10 @@
         "x86_64-darwin" "x86_64-linux"
       ];
 
-
       overlays = [
         haskellNix.overlay
         (final: prev: {
-          gyehoek-wasmtime-wrapper = final.callPackage ./wasmtime.nix {};
+          shake-wrapper = final.callPackage ./shake-wrapper.nix {};
           gyehoek-runtime = final.callPackage ./runtime {};
           gyehoek = final.haskell-nix.project' {
             src = ./.;
@@ -29,13 +28,10 @@
               packages.gyehoek.components.tests.test.preCheck =
                 let
                   bin = [
-                    pkgs.gyehoek-wasmtime-wrapper
-                    pkgs.git
+                    pkgs.git # tasty uses git diff
                   ];
                 in ''
-                  # Wasmtime requires a cache in $HOME. This is less
-                  # painful than reconfiguring the cache location.
-                  export HOME=$(mktemp -d)
+                  export GYEHOEK_RUNTIME=${lib.getExe final.gyehoek-runtime}
                   export PATH=${lib.makeBinPath bin}:$PATH
                 '';
             })];
@@ -50,14 +46,14 @@
               };
               buildInputs = with final; [
                 haskellPackages.cabal-fmt
-                self.packages.${final.stdenv.hostPlatform.system}.shake
+                shake-wrapper
                 wabt
                 nodejs
                 wasm-tools
                 wac-cli
                 guile
-                gyehoek-wasmtime-wrapper
                 rust-analyzer
+                wasmtime
               ];
             };
           };
@@ -89,7 +85,7 @@
         hf.packages.${system} // lib.fix (packages: {
           gyehoek = hf.packages.${system}."gyehoek:exe:gyehoek";
           default = packages.gyehoek;
-          shake = pkgs.callPackage ./shake-wrapper.nix {};
+          inherit (pkgs) gyehoek-runtime shake-wrapper;
         }));
 
       devShells = each-system