diff --git a/util/check-dev-env b/util/check-dev-env
index d0e4e0ab..81a6c22b 100755
--- a/util/check-dev-env
+++ b/util/check-dev-env
@@ -28,6 +28,7 @@ my @required_modules = qw(
    Test::More
    Time::HiRes
    Time::Local
+   JSON
 );
 
 # CentOS doesn't seem to have this in its repo.