Leiningen is a build automation tool specifically designed for Clojure projects. It simplifies the management of dependencies and automates various development tasks, making it easier for developers to configure and build Clojure applications. Leiningen offers features such as project scaffolding, testing, packaging, and deployment, as well as integration with the Clojure ecosystem's libraries and tools. The tool streamlines the project workflow by using a straightforward command-line interface.