diff --git a/pkgs/clan-cli/default.nix b/pkgs/clan-cli/default.nix
index f22a26ed2..81820c858 100644
--- a/pkgs/clan-cli/default.nix
+++ b/pkgs/clan-cli/default.nix
@@ -195,48 +195,6 @@ pythonRuntime.pkgs.buildPythonApplication {
               pkgs.coreutils
               pkgs.nix
             ];
-            closureInfo = pkgs.closureInfo {
-              rootPaths = [
-                templateDerivation
-                pkgs.bash
-                pkgs.coreutils
-                pkgs.jq.dev
-                pkgs.stdenv
-                pkgs.stdenvNoCC
-                pkgs.shellcheck-minimal
-              ];
-            };
-          }
-          ''
-            set -euo pipefail
-            cp -r ${sourceWithTests} ./src
-            chmod +w -R ./src
-            cd ./src
-
-            ${setupNixInNix}
-
-            export CLAN_CORE_PATH=${clan-core-path}
-            export PYTHONWARNINGS=error
-
-            # limit build cores to 16
-            jobs="$((NIX_BUILD_CORES>16 ? 16 : NIX_BUILD_CORES))"
-
-            python -m pytest -m "not impure and with_core" ./clan_cli -n $jobs
-            touch $out
-          '';
-    }
-    // lib.optionalAttrs (!stdenv.isDarwin) {
-      # disabled on macOS until we fix all remaining issues
-      clan-lib-pytest =
-        runCommand "clan-lib-pytest"
-          {
-            nativeBuildInputs = testDependencies;
-            buildInputs = [
-              pkgs.bash
-              pkgs.coreutils
-              pkgs.nix
-
-            ];
             closureInfo = pkgs.closureInfo {
               rootPaths = [
                 templateDerivation
@@ -268,10 +226,11 @@ pythonRuntime.pkgs.buildPythonApplication {
             export NIXPKGS=${nixpkgs}
             export NIX_SELECT=${nix-select}
 
-            # limit build cores to 4
-            jobs="$((NIX_BUILD_CORES>4 ? 4 : NIX_BUILD_CORES))"
+            # limit build cores to 16
+            jobs="$((NIX_BUILD_CORES>16 ? 16 : NIX_BUILD_CORES))"
 
-            python -m pytest -m "with_core" ./clan_lib -n $jobs
+            # Run all tests with core marker
+            python -m pytest -m "not impure and with_core" -n $jobs ./clan_cli ./clan_lib
             touch $out
           '';
     };