How Clojure Installation Works

Installing Clojure is not like installing a separate runtime beside the JVM. Clojure is a JVM language, and the language itself is distributed as a JAR dependency. The Clojure command-line tools give you convenient commands for starting a REPL, building classpaths, downloading dependencies, and running Clojure code.

For a Java engineer, the useful mental model is:

CLI Version Versus Language Version

The official Clojure install guide treats the Clojure CLI version and Clojure language version as separate. That distinction matters in real projects:

• the CLI has its own version number
• the language dependency has its own version number
• any CLI version can download and use different Clojure language versions
• the leading parts of the CLI version indicate the default language version used by a plain REPL unless project configuration says otherwise

This is different from many Java tool installs, where the command version and language/runtime version feel tightly bundled.

clj Versus clojure

You will see two commands:

1clj
2clojure

Use clj for interactive REPL work when it is available. Use clojure when running explicit command-line operations, scripts, or aliases. They are closely related, but clj is the friendlier interactive entry point on platforms where it wraps line-editing behavior.

What A Successful Install Gives You

After the CLI is installed, you should be able to:

1clojure --version
2clj -h
3clojure -Spath

These prove different things:

If Java is missing or misconfigured, Clojure commands will fail before your code is involved. Always verify Java first.

The Installation Goal

The goal is not to memorize installer details. The goal is to reach a stable loop:

1. Java is on the path.
2. clojure and clj are available.
3. a REPL starts.
4. dependencies resolve.
5. your editor can connect to the same project JVM.

Once those are true, you can learn Clojure by evaluating real code instead of guessing from static examples.

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