diff --git a/Dockerfile b/Dockerfile
index 8fdac0c..396f592 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 FROM golang:1.18.1-alpine
-RUN apk add git bash curl poppler-utils gcc musl-dev xmlstarlet parallel libxml2-utils
+RUN apk add git bash curl poppler-utils gcc musl-dev xmlstarlet parallel libxml2-utils coreutils
 
 # build
 WORKDIR /app