diff --git a/src/propeller/problems/boolean/mul3.cljc b/src/propeller/problems/boolean/mul3.cljc
index 4ef4dc6..b027808 100644
--- a/src/propeller/problems/boolean/mul3.cljc
+++ b/src/propeller/problems/boolean/mul3.cljc
@@ -1,3 +1,5 @@
+;; EXPERIMENTAL: Code in this file is still under development. It may be broken. Expect changes.
+
 (ns propeller.problems.boolean.mul3
   (:require [propeller.genome :as genome]
             [propeller.push.interpreter :as interpreter]
diff --git a/src/propeller/problems/boolean/mul4.cljc b/src/propeller/problems/boolean/mul4.cljc
index 0e84406..18a4038 100644
--- a/src/propeller/problems/boolean/mul4.cljc
+++ b/src/propeller/problems/boolean/mul4.cljc
@@ -1,3 +1,5 @@
+;; EXPERIMENTAL: Code in this file is still under development. It may be broken. Expect changes.
+
 (ns propeller.problems.boolean.mul4
   (:require [propeller.genome :as genome]
             [propeller.push.interpreter :as interpreter]