diff --git a/lib/impl/helpers.nix b/lib/impl/helpers.nix
index 66a42cf..4b08c7f 100644
--- a/lib/impl/helpers.nix
+++ b/lib/impl/helpers.nix
@@ -2,7 +2,21 @@
   pkgs,
   lib,
 } @ args: let
-  inherit (lib) types isAttrs filterAttrs mapAttrs mkOption mkOptionType isType literalExpression pipe;
+  inherit
+    (lib)
+    types
+    isAttrs
+    filterAttrs
+    mapAttrs
+    mkOption
+    mkOptionType
+    isType
+    literalExpression
+    pipe
+    hasInfix
+    concatMapAttrs
+    optionalAttrs
+    ;
 in rec {
   prepend = key: arr: job: {
     ${key} = arr ++ (job.${key} or []);
@@ -33,10 +47,10 @@ in rec {
 
   # filter job's variables to either only those containing store paths
   # or those that do not
-  filterJobVariables = nix: job:
-    lib.concatMapAttrs (
+  filterJobVariables = shouldContain: job:
+    concatMapAttrs (
       name: value:
-        lib.optionalAttrs ((lib.hasInfix "/nix/store/" value) == nix) {
+        optionalAttrs ((hasInfix "/nix/store/" value) == shouldContain) {
           ${name} = value;
         }
     )
diff --git a/lib/impl/jobPatched.nix b/lib/impl/jobPatched.nix
index 4bf0e00..9997caa 100644
--- a/lib/impl/jobPatched.nix
+++ b/lib/impl/jobPatched.nix
@@ -16,28 +16,16 @@ in
       (prependToBeforeScript ["source setup_nix_ci \"gitlab-ci:pipeline:${pipelineName}:job-deps:${key}\""] job)
       // (appendToAfterScript ["finalize_nix_ci"] job)
     ))
-    // optionalAttrs nixConfig.enable (
-      (let
-        variables =
-          (filterJobVariables false job)
-          // optionalAttrs nixConfig.enableRunnerCache {
-            NIX_CI_CACHE_STRATEGY = "runner";
-          };
-      in
-        # filter empty variables
-        optionalAttrs (variables != {}) {
-          inherit variables;
-        })
-      // (let
-        cache =
-          (toList (job.cache or []))
-          ++ (optional nixConfig.enableRunnerCache {
-            key = nixConfig.runnerCacheKey;
-            paths = [".nix-cache/"];
-          });
-      in
-        # filter empty cache
-        optionalAttrs (cache != []) {
-          inherit cache;
-        })
-    )
+    // optionalAttrs nixConfig.enable {
+      variables =
+        (filterJobVariables false job)
+        // optionalAttrs nixConfig.enableRunnerCache {
+          NIX_CI_CACHE_STRATEGY = "runner";
+        };
+      cache =
+        (toList (job.cache or []))
+        ++ (optional nixConfig.enableRunnerCache {
+          key = nixConfig.runnerCacheKey;
+          paths = [".nix-cache/"];
+        });
+    }