diff --git a/Dockerfile b/Dockerfile
index 2d80f01..c74e310 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:9.6-slim
+FROM curlimages/curl:7.68.0
 
 LABEL "com.github.actions.name"="Post Slack messages"
 LABEL "com.github.actions.description"="Post Slack messages from your own bot"
@@ -10,7 +10,5 @@ LABEL repository="http://github.com/pullreminders/slack-action"
 LABEL homepage="http://github.com/pullreminders/slack-action"
 LABEL maintainer="Abi Noda <abi@pullreminders.com>"
 
-RUN apt-get update && apt-get install -y curl
-
 ADD entrypoint.sh /entrypoint.sh
 ENTRYPOINT ["/entrypoint.sh"]