diff --git a/contrib/pyln-proto/requirements.txt b/contrib/pyln-proto/requirements.txt
index b8b491ddc..bf7ed6aae 100644
--- a/contrib/pyln-proto/requirements.txt
+++ b/contrib/pyln-proto/requirements.txt
@@ -2,5 +2,5 @@ bitstring==3.1.6
 cryptography==3.2
 coincurve==13.0.0
 base58==1.0.2
-mypy
+mypy==0.790
 pysocks==1.7.*