diff --git a/docker/golang/Dockerfile b/docker/golang/Dockerfile
index ead91ee..4d16eb6 100644
--- a/docker/golang/Dockerfile
+++ b/docker/golang/Dockerfile
@@ -3,7 +3,7 @@ FROM golang:1.6.2-alpine
 MAINTAINER Bo-Yi Wu <appleboy.tw@gmail.com>
 
 RUN apk update \
-  && apk add git make curl && rm -rf /var/cache/apk/*
+  && apk add git make curl perl && rm -rf /var/cache/apk/*
 
 # install glide package management.
 RUN curl https://glide.sh/get | sh
diff --git a/script/coverage.sh b/script/coverage.sh
index a7e6f99..f6b5946 100755
--- a/script/coverage.sh
+++ b/script/coverage.sh
@@ -84,10 +84,11 @@ generate_cloc_report() {
     linux*)
       which cloc || apt-get install cloc ;;
     *)
-      output "unknown: $OSTYPE" 1 ;;
+      curl https://raw.githubusercontent.com/AlDanial/cloc/master/cloc -o /usr/bin/cloc
+      chmod 755 /usr/bin/cloc
   esac
 
-  cloc --by-file --xml --out=${cloc_report} --exclude-dir=vendor,Godeps .
+  cloc --by-file --xml --out=${cloc_report} --exclude-dir=vendor,Godeps,.cover .
 }
 
 case "$1" in