diff --git a/Dockerfile b/Dockerfile
index 5a6d416..f0d78c5 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get -y update \
         hunspell-en-us \
         sed \
         util-linux \
+        bsdmainutils \
     && rm -Rf /var/lib/apt/lists/*
 
 RUN python -m pip install -r /opt/checker/requirements.txt