# Making Changes To Standard Libraries Everything in the [lib](https://github.com/ruby/ruby/tree/master/lib) directory is mirrored from a standalone repository into the Ruby repository. If you'd like to make contributions to standard libraries, do so in the standalone repositories, and the changes will be automatically mirrored into the Ruby repository. For example, CSV lives in [a separate repository](https://github.com/ruby/csv) and is mirrored into [Ruby](https://github.com/ruby/ruby/tree/master/lib/csv). ## Maintainers You can find the list of maintainers [here](https://docs.ruby-lang.org/en/master/maintainers_md.html#label-Maintainers). ## Build First, install its dependencies using: ```shell bundle install ``` ### Libraries with C-extension If the library has a `/ext` directory, it has C files that you need to compile with: ```shell bundle exec rake compile ``` ## Running tests All standard libraries use [test-unit](https://github.com/test-unit/test-unit) as the test framework. To run all tests: ```shell bundle exec rake test ``` To run a single test file: ```shell bundle exec rake test TEST="test/test_foo.rb" ``` To run a single test case: ```shell bundle exec rake test TEST="test/test_foo.rb" TESTOPS="--name=/test_mytest/" ```