diff --git a/.dockerignore b/.dockerignore
index bbc584d9f..4c1f0b007 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -12,22 +12,23 @@ postgresql
 elasticsearch
 redis
 
+
+# Ignore public assets
+public/uploads
+public/assets
+
 # Ignore all logfiles and tempfiles.
 log
 *.log
 tmp
 
-public/uploads
-public/assets
-
+# Ignore platform dependent files
 *.DS_Store
 .idea
 
 # PDF invoices
 invoices
 
-.DS_Store
-
 # Development files
 .vagrant
 Vagrantfile
@@ -35,6 +36,7 @@ provision
 .git*
 Dockerfile
 docker-compose*
+test
 
 # Docs
 *.md
diff --git a/Dockerfile b/Dockerfile
index 3a15f3f78..5ac82d08d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -4,7 +4,9 @@ MAINTAINER peng@sleede.com
 # Install upgrade system packages
 RUN apk update && apk upgrade && \
 # Install runtime apk dependencies
-    apk add --update curl \
+    apk add --update \
+      bash \
+      curl \
       nodejs \
       yarn \
       imagemagick \
@@ -19,7 +21,8 @@ RUN apk update && apk upgrade && \
       libxslt-dev \
       libidn-dev && \
 # Install buildtime apk dependencies
-    apk add --update --no-cache --virtual .build-deps alpine-sdk \
+    apk add --update --no-cache --virtual .build-deps \
+      alpine-sdk \
       build-base \
       linux-headers \
       git \
diff --git a/Gemfile b/Gemfile
index e43d5ba2f..697e34052 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,6 +3,8 @@ source 'https://rubygems.org'
 gem 'compass-rails', '2.0.4'
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '4.2.11.1'
+# Use Puma as web server
+gem 'puma', '3.10.0'
 # Use SCSS for stylesheets
 gem 'sass-rails', '5.0.1'
 
@@ -45,7 +47,6 @@ group :development do
   gem 'foreman'
   # Preview mail in the browser
   gem 'mailcatcher'
-  gem 'puma'
   gem 'rb-readline'
 end
 
diff --git a/Gemfile.lock b/Gemfile.lock
index d8361c6be..10cddb765 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -517,7 +517,7 @@ DEPENDENCIES
   prawn
   prawn-table
   protected_attributes
-  puma
+  puma (= 3.10.0)
   pundit
   rack-protection (= 1.5.5)
   railroady