dev.Dockerfile in icalia-foresight-0.0.3 vs dev.Dockerfile in icalia-foresight-0.0.4

@@ -1,11 +1,24 @@
-# 1: Use ruby 2.3.3 as base:
-FROM ruby:2.3.3
+# 1: Use ruby 2.4.1 as base:
+FROM ruby:2.4.1-alpine
 
-# 2: We'll set this gem path as the working directory
+# 2: We'll set this gem's lib path as the working directory
 WORKDIR /usr/src/lib
 
 # 3: We'll set the working dir as HOME and add the app's binaries path to $PATH:
-ENV HOME=/usr/src/lib PATH=/usr/src/lib/bin:$PATH
+# NOTE: The PAGER variable allows Pry to work on alpine linux.
+# See https://github.com/pry/pry/issues/1494
+ENV HOME=/usr/src/lib PATH=/usr/src/lib/bin:$PATH PAGER='busybox less'
 
 # 4: Set the default command:
 CMD ["guard"]
+
+# --- Install development and runtime dependencies: ---
+
+# 6: Install the development & runtime packages:
+RUN set -ex && apk add --no-cache \
+  build-base \
+  git \
+  ca-certificates \
+  openssl \
+  tzdata \
+  su-exec