diff --git a/pkgs/racket-test-core/tests/racket/optimize.rktl b/pkgs/racket-test-core/tests/racket/optimize.rktl
index 1aa59ed2a5..01ab2b1f16 100644
--- a/pkgs/racket-test-core/tests/racket/optimize.rktl
+++ b/pkgs/racket-test-core/tests/racket/optimize.rktl
@@ -9,7 +9,10 @@
          racket/unsafe/undefined
          racket/unsafe/ops
          compiler/zo-parse
-         compiler/zo-marshal)
+         compiler/zo-marshal
+         ;; `random` from `racket/base is a Racket function, which makes
+         ;; compilation less predictable than a primitive
+         (only-in '#%kernel random))
 
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