install build-essential to leapcode/ruby to install gems from source

diff --git a/docker/ruby/Dockerfile b/docker/ruby/Dockerfile
index 7403ac8..78b6ef6 100644 (file)
--- a/docker/ruby/Dockerfile
+++ b/docker/ruby/Dockerfile
@@ -9,6 +9,7 @@ RUN apt-get update \
   && apt-get install -y --no-install-recommends \
     ruby \
     ruby-dev \
+    build-essential \
     rsync \
     openssh-client \
     openssl \