```ruby
# coding: utf-8
lib = File.expand_path('../lib', __FILE__)
$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
require 'engine_cart/version'

Gem::Specification.new do |spec|
  spec.name          = "engine_cart"
  spec.version       = EngineCart::VERSION
  spec.authors       = ["Chris Beer"]
  spec.email         = ["cabeer@stanford.edu"]
  spec.description   = %q{Helper for testing Rails Engines sanely}
  spec.summary       = %q{Helper for testing Rails Engines sanely}
  spec.homepage      = "https://github.com/cbeer/engine_cart"
  spec.license       = "MIT"

  spec.files         = `git ls-files`.split($/)
  spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }
  spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
  spec.require_paths = ["lib"]

  spec.add_dependency "rails"
  spec.add_dependency "bundler", "~> 1.5"
  spec.add_development_dependency "rake"
  spec.add_development_dependency "rspec"
end
```

Remove a hard dependency on the bundler gem, since it is baked into ruby 2.6
user
```ruby
# coding: utf-8
lib = File.expand_path('../lib', __FILE__)
$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
require 'engine_cart/version'

Gem::Specification.new do |spec|
  spec.name          = "engine_cart"
  spec.version       = EngineCart::VERSION
  spec.authors       = ["Chris Beer"]
  spec.email         = ["cabeer@stanford.edu"]
  spec.description   = %q{Helper for testing Rails Engines sanely}
  spec.summary       = %q{Helper for testing Rails Engines sanely}
  spec.homepage      = "https://github.com/cbeer/engine_cart"
  spec.license       = "MIT"

  spec.files         = `git ls-files`.split($/)
  spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }
  spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
  spec.require_paths = ["lib"]

  spec.add_dependency "rails"
  spec.add_development_dependency "rake"
  spec.add_development_dependency "rspec"
end
```
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