Add materialized files

Author: hamishmack

ci-lib.nix

@@ -32,10 +32,11 @@ rec {
   # derivations.
   filterAttrsOnlyRecursive = pred: set:
     lib.mapAttrs (name: v:
-      if builtins.isAttrs v
-          && !(lib.isDerivation v || v ? outPath)
-        then if pred name v
+      if pred name v
+        then
+          if builtins.isAttrs v
+              && !lib.isDerivation v
             then filterAttrsOnlyRecursive pred v
-            else {}
-        else v.outPath or v) set;
+            else v
+        else {}) set;
 }