diff --git a/test/external/fuzz_shapetracker_math.py b/test/external/fuzz_shapetracker_math.py
index ae7c2dc2e7..3926fe8cf0 100644
--- a/test/external/fuzz_shapetracker_math.py
+++ b/test/external/fuzz_shapetracker_math.py
@@ -1,4 +1,5 @@
 import random
+from typing import Tuple
 from tqdm import trange
 from tinygrad.helpers import getenv, DEBUG, colored
 from tinygrad.shape.shapetracker import ShapeTracker
@@ -6,7 +7,7 @@ from test.external.fuzz_shapetracker import shapetracker_ops
 from test.external.fuzz_shapetracker import do_permute, do_reshape_split_one, do_reshape_combine_two, do_flip, do_pad
 from test.unit.test_shapetracker_math import st_equal, MultiShapeTracker
 
-def fuzz_plus():
+def fuzz_plus() -> Tuple[ShapeTracker, ShapeTracker]:
   m = MultiShapeTracker([ShapeTracker.from_shape((random.randint(1, 10), random.randint(1, 10), random.randint(1, 10)))])
   for _ in range(4): random.choice(shapetracker_ops)(m)
   backup = m.sts[0]
@@ -18,7 +19,7 @@ def fuzz_plus():
 # shrink and expand aren't invertible, and stride is only invertible in the flip case
 invertible_shapetracker_ops = [do_permute, do_reshape_split_one, do_reshape_combine_two, do_flip, do_pad]
 
-def fuzz_invert():
+def fuzz_invert() -> Tuple[ShapeTracker, ShapeTracker]:
   start = ShapeTracker.from_shape((random.randint(1, 10), random.randint(1, 10), random.randint(1, 10)))
   m = MultiShapeTracker([start])
   for _ in range(8): random.choice(invertible_shapetracker_ops)(m)
@@ -33,6 +34,10 @@ if __name__ == "__main__":
     for _ in trange(total, desc=f"{fuzz}"):
       st1, st2 = fuzz()
       eq = st_equal(st1, st2)
+      if getenv("CHECK_NEQ") and eq and st1.simplify() != st2.simplify():
+        print(colored("same but unequal", "yellow"))
+        print(st1.simplify())
+        print(st2.simplify())
       if DEBUG >= 1:
         print(f"EXP: {st1}")
         print(f"GOT: {st2}")