# Making Changes To Standard Libraries¶ ↑

Everything in the 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 and is mirrored into Ruby.

## Maintainers¶ ↑

You can find the list of maintainers here.

## Build¶ ↑

First, install its dependencies using:

    bundle install

### Libraries with C-extension¶ ↑

If the library has a `/ext` directory, it has C files that you need to compile with:

    bundle exec rake compile

## Running tests¶ ↑

All standard libraries use test-unit as the test framework.

To run all tests:

    bundle exec rake test

To run a single test file:

    bundle exec rake test TEST="test/test_foo.rb"

To run a single test case:

    bundle exec rake test TEST="test/test_foo.rb" TESTOPS="--name=/test_mytest/"