The simplest way to get started with Compojure is to use Leiningen, the standard Clojure build tool. If you haven't already, download and install Leiningen. You'll need Leiningen 2.0.0 or later for these next instructions to work.

Next, create a new project using the "compojure" template:

lein new compojure hello-world

This will create a basic project skeleton containing a minimal web application.

You can now change into the project directory, and start a development server using Leiningen:

cd hello-world
lein ring server-headless

The dev server will start up on port 3000. If you make a change to one of the source files, it will automatically reload it for you.

You can also create a runnable jar file of your web application:

lein ring uberjar

copy the resulting standalone jar to wherever you like, and run it in the usual way:

java -jar path/to/hello-world-0.1.0-standalone.jar