https://github.com/heroku/heroku-buildpack-clojure
Heroku's classic buildpack for Clojure applications.
https://github.com/heroku/heroku-buildpack-clojure
buildpack clojure heroku heroku-languages
Last synced: 15 days ago
JSON representation
Heroku's classic buildpack for Clojure applications.
- Host: GitHub
- URL: https://github.com/heroku/heroku-buildpack-clojure
- Owner: heroku
- License: mit
- Created: 2011-05-14T06:33:48.000Z (almost 15 years ago)
- Default Branch: main
- Last Pushed: 2026-03-25T23:21:56.000Z (23 days ago)
- Last Synced: 2026-03-26T12:35:30.224Z (22 days ago)
- Topics: buildpack, clojure, heroku, heroku-languages
- Language: Ruby
- Homepage: https://devcenter.heroku.com/categories/clojure-support
- Size: 549 KB
- Stars: 117
- Watchers: 99
- Forks: 114
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
- Codeowners: .github/CODEOWNERS
Awesome Lists containing this project
- awesome-cnb - Clojure
- awesome - heroku/heroku-buildpack-clojure - Heroku's classic buildpack for Clojure applications. (<a name="Ruby"></a>Ruby)
README
# Heroku Buildpack: Clojure (Leiningen) [](https://github.com/heroku/heroku-buildpack-clojure/actions/workflows/ci.yml)
This is the official [Heroku buildpack](https://devcenter.heroku.com/articles/buildpacks) for apps that use [Leiningen](https://leiningen.org/) as their build tool. It's primarily used to build [Clojure](https://clojure.org/) applications.
If you're using a different JVM build tool, use the appropriate buildpack:
* [Java buildpack](https://github.com/heroku/heroku-buildpack-java) for [Maven](https://maven.apache.org/) projects
* [Gradle buildpack](https://github.com/heroku/heroku-buildpack-gradle) for [Gradle](https://gradle.org/) projects
* [Scala buildpack](https://github.com/heroku/heroku-buildpack-scala) for [sbt](https://www.scala-sbt.org/) projects
## Table of Contents
- [Supported Leiningen Versions](#supported-leiningen-versions)
- [Getting Started](#getting-started)
- [Application Requirements](#application-requirements)
- [Configuration](#configuration)
- [OpenJDK Version](#openjdk-version)
- [Leiningen Version](#leiningen-version)
- [Buildpack Configuration](#buildpack-configuration)
- [Documentation](#documentation)
## Supported Leiningen Versions
This buildpack officially supports Leiningen `2.x`. Leiningen `1.x` is no longer supported.
## Getting Started
See the [Getting Started with Clojure on Heroku](https://devcenter.heroku.com/articles/getting-started-with-clojure) tutorial.
## Application Requirements
Your app requires a `project.clj` file in the root directory with `:min-lein-version "2.0.0"` or higher. It's recommended to also configure `:uberjar-name` in your `project.clj`.
## Configuration
### OpenJDK Version
Specify an OpenJDK version by creating a `system.properties` file in the root of your project directory and setting the `java.runtime.version` property. See the [Java Support article](https://devcenter.heroku.com/articles/java-support#supported-java-versions) for available versions and configuration instructions.
### Leiningen Version
The buildpack uses Leiningen `2.12.0` by default for projects that specify `:min-lein-version "2.0.0"` or higher in their `project.clj`.
To use a specific Leiningen version, you can include a `bin/lein` script in your repository. The buildpack will detect and use this script instead of the default Leiningen installation.
### Buildpack Configuration
Configure the buildpack by setting environment variables:
| Environment Variable | Description | Default |
|---------------------|-------------|---------|
| `LEIN_BUILD_TASK` | Leiningen task to execute | `uberjar` (if `:uberjar-name` is set) or `with-profile production compile :all` |
| `LEIN_INCLUDE_IN_SLUG` | Include Leiningen in the slug for runtime use | `no` |
| `CLOJURE_CLI_VERSION` | Clojure CLI tools version | `1.12.4.1597` |
You can also override the default build behavior by including a `bin/build` script in your repository. The buildpack will execute this script instead of the default build command.
## Documentation
For more information about using Clojure on Heroku, see the [Clojure Support](https://devcenter.heroku.com/categories/clojure-support) documentation on Dev Center.