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nREPL is a Clojure *n*etwork REPL that
provides a REPL server and client, along with some common APIs
of use to IDEs and other tools that may need to evaluate Clojure
code in remote environments.

nREPL powers [many well-known development tools](https://nrepl.org/nrepl/usage/clients.html).

## Usage

* Start an nREPL server (e.g. with `lein repl`)
* Connect to the server using any nREPL client (e.g. CIDER, Calva, vim-fireplace)
* Start hacking!

See the [documentation](https://nrepl.org/nrepl/usage/server.html) for way information on the subject.

## API Documentation

You can find nREPL's API documentation on [cljdoc](https://cljdoc.org/d/nrepl/nrepl/CURRENT).

## Status

Extremely stable. nREPL's protocol and API are rock-solid and battle
tested. nREPL's team pledges to evolve them only in
backwards-compatible ways.

That being said, there were a few organizational changes related to
the transition out of clojure-contrib that everyone has to keep in
mind:

* `[nrepl "0.3.1"]` is a drop-in replacement for
  `[org.clojure/tools.nrepl "0.2.13"]` (notice the different artifact coordinates).
* `[nrepl "0.4.0"]` changes the namespaces from `clojure.tools.nrepl.*` to
`nrepl.*`.

A later `1.0.0` release will include fixes for all previously-reported
but languishing nREPL issues. Future releases will focus on supporting
the needs of the essential tools of the Clojure(Script) ecosystem
(e.g. Leiningen, Boot, CIDER, Cursive).

## FAQ

### How is this different from the "contrib" [tools.nrepl](https://github.com/clojure/tools.nrepl/) project?

Check the brief history of nREPL, available
[here](https://nrepl.org/nrepl/about/history.html).

### How does nREPL compare to other REPL servers (e.g. `prepl`)?

Check out [this detailed comparison](https://nrepl.org/nrepl/alternatives.html).

### Does nREPL support ClojureScript?

Yes and no. The reference nREPL implementation is Clojure-specific, but it can be extended with ClojureScript support
via the Piggieback middleware. In the future there may be implementations of nREPL that target ClojureScript directly.

### Does nREPL support other programming languages besides Clojure?

The nREPL protocol is language-agnostic and implementations of nREPL servers exist for [several programming languages](https://nrepl.org/nrepl/beyond_clojure.html).
Implementing new nREPL servers is [pretty simple](https://nrepl.org/nrepl/building_servers.html).

## Contributors

This project exists thanks to all the people who contribute.
<a href="https://github.com/nrepl/nrepl/graphs/contributors"><img src="https://opencollective.com/nrepl/contributors.svg?width=890&button=false" /></a>


## Backers

Thank you to all our backers! 🙏 [[Become a backer](https://opencollective.com/nrepl#backer)]

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## Sponsors

Support this project by becoming a sponsor. Your logo will show up here with a link to your website. [[Become a sponsor](https://opencollective.com/nrepl#sponsor)]

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## License

Copyright © 2010-2021 Chas Emerick, Bozhidar Batsov and contributors.

Licensed under the EPL. (See the file epl.html.)