diff --git a/requirements_dev.txt b/requirements_dev.txt
index 910635e288de911b3d884a06e610fd2868abd1fe..f0486d78d9de949b1735de6fbf7c3f402fc48fff 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -9,7 +9,7 @@ recordtype>=1.3
 matplotlib>=3.0.2
 Pillow>=5.4.1
 CairoSVG>=2.3.1
-msgpack>=0.6.1
+msgpack==0.6.1
 msgpack-numpy>=0.4.4.0
 svgutils>=0.3.1
 pyarrow>=0.13.0