diff --git a/ci.nix b/ci.nix
index 8ddd208d..b7e8da5a 100644
--- a/ci.nix
+++ b/ci.nix
@@ -13,7 +13,7 @@ with builtins; let
   isReserved = n: n == "lib" || n == "overlays" || n == "modules";
   isDerivation = p: isAttrs p && p ? type && p.type == "derivation";
   isBuildable = p: !(p.meta.broken or false) && p.meta.license.free or true;
-  isCacheable = p: !(p.preferLocalBuild or false) && pkgs.lib.any (prov: !prov.isSource) (p.meta.sourceProvenance or []);
+  isCacheable = p: !(p.preferLocalBuild or false) && !(pkgs.lib.any (prov: !prov.isSource) (p.meta.sourceProvenance or []));
   shouldRecurseForDerivations = p:
     isAttrs p && p.recurseForDerivations or false;