diff --git a/requirements.txt b/requirements.txt
index abb96f21a7db81c90a1787ef84122790ce3836be..6954e374c18b516c970e6546f8857a617e8ecb99 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 numpy
-git+https://github.com/inducer/pytools.git
+git+https://github.com/inducer/pytools.git@memoize-in-complex-identifiers
 git+https://github.com/inducer/pymbolic.git
 git+https://github.com/inducer/islpy.git
 git+https://github.com/inducer/pyopencl.git