diff --git a/Dockerfile b/Dockerfile
index ea925e1..1887590 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -20,6 +20,7 @@ RUN apk add --update --no-cache \
       build-base="${BUILD_BASE_VERSION}" \
       gcc="${GCC_VERSION}" \
       ruby="${RUBY_VERSION}" \
+      ruby-dev="${RUBY_VERSION}" \
       git="${GIT_VERSION}" \
       openssh-keygen="${OPENSSH_KEYGEN_VERSION}" \
     && \