# Polyphony: Fine-Grained Concurrency for Ruby
> Polyphony \| pəˈlɪf\(ə\)ni \|
>
> 1. _Music_ the style of simultaneously combining a number of parts, each
> forming an individual melody and harmonizing with each other.
>
> 2. _Programming_ a Ruby gem for concurrent programming focusing on performance
> and developer happiness.
## What is Polyphony?
Polyphony is a library for building concurrent applications in Ruby. Polyphony
harnesses the power of [Ruby fibers](https://rubyapi.org/3.2/o/fiber) to provide
a cooperative, sequential coroutine-based concurrency model. Under the hood,
Polyphony uses [io_uring](https://unixism.net/loti/what_is_io_uring.html) or
[libev](https://github.com/enki/libev) to maximize I/O performance.
## Features
* Ruby fibers as the main unit of concurrency.
* [Structured concurrency](https://en.wikipedia.org/wiki/Structured_concurrency)
coupled with robust exception handling.
* Message passing between fibers, even across threads!
* High-performance I/O using the core Ruby I/O classes and
[io_uring](https://unixism.net/loti/what_is_io_uring.html) with support for
[advanced I/O patterns](docs/advanced-io.md).
## Usage
- [Installation](docs/installation.md)
- [Overview](docs/overview.md)
- [Tutorial](docs/tutorial.md)
- [All About Cancellation: How to Stop Concurrent Operations](docs/cancellation.md)
- [Advanced I/O with Polyphony](docs/advanced-io.md)
- [Cheat-Sheet](docs/cheat-sheet.md)
- [FAQ](docs/faq.md)
## Technical Discussion
- [Concurrency the Easy Way](docs/concurrency.md)
- [How Fibers are Scheduled](docs/fiber-scheduling.md)
- [Exception Handling](docs/exception-handling.md)
- [Extending Polyphony](docs/extending.md)
- [Polyphony's Design](docs/design-principles.md)
## Examples
For examples of specific use cases you can consult the [bundled
examples](https://github.com/digital-fabric/polyphony/tree/master/examples) in
Polyphony's GitHub repository.
## Contributing to Polyphony
Issues and pull requests will be gladly accepted. Please use the [Polyphony git
repository](https://github.com/digital-fabric/polyphony) as your primary point
of departure for contributing.