diff --git a/requirements.txt b/requirements.txt
index a8885ae00..03d14cb97 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,9 +1,9 @@
 cython
-cymem >= 1.11
+cymem == 1.11
 pathlib
-preshed
+preshed == 0.37
 thinc == 1.76
-murmurhash
+murmurhash == 0.24
 unidecode
 numpy
 wget