gemspec

This is the gemspec provided by the enginex gem when I used it to create the 'api' engine

# Provide a simple gemspec so you can easily use your enginex
# project in your rails apps through git.
Gem::Specification.new do |s|
  s.name = "api"
  s.summary = "Insert Api summary."
  s.description = "Insert Api description."
  s.files = Dir["{app,lib,config}/**/*"] + ["MIT-LICENSE", "Rakefile", "Gemfile", "README.rdoc"]
  s.version = "0.0.1"
end

Here is my main application's Gemfile
source 'https://rubygems.org'

gem 'api', path: '../api/'
gem 'rails', '4.2.5.1'
gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.1.0'
gem 'jquery-rails'
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0', group: :doc

group :development, :test do
  gem 'byebug'
end

group :development do
  gem 'web-console', '~> 2.0'
end