postinstall.sh

#!/usr/bin/env bash

# skip installing docs
echo gem: --no-ri --no-rdoc > ~/.gemrc
echo "export SSL_CERT_FILE=/lib/ruby/site_ruby/2.2.0/rubygems/ssl_certs/ca-bundle.pem" > ~/.profile
echo "export PATH=\"/lib/sqlite3/bin:\$PATH\"" > ~/.profile

# install sqlite
cd /src/sqlite3
./configure --prefix=/lib/sqlite3
make
make install
gem install sqlite3-ruby --platform=ruby -- --with-sqlite3-dir=/lib/sqlite3

# install rails (we want to offer portable*Rails*)
gem install rails

#
cp /bin/gem.bat /bin/bin.template && for file in /bin/*.bat; do cp /bin/bin.template $file; done

# show the version
rails -v

# install rails to make sure all the required gems are installed for a default config
rails new murb

# and remove the mess
rm -rf murb