diff --git a/requirements_dev.txt b/requirements_dev.txt
index 1ba26e1..b87a589 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -10,3 +10,4 @@ twine==1.10.0
 
 pytest==3.4.2
 pytest-runner==2.11.1
+pygments>=2.7.4 # not directly required, pinned by Snyk to avoid a vulnerability