Java and Kotlin by IntelliJ IDEA: The LSP-Based Extension Reaches Release Candidate

Two months ago, we announced the preview of Java and Kotlin by IntelliJ IDEA – an LSP-based extension that brings IntelliJ IDEA’s Java and Kotlin intelligence to third-party editors, starting with VS Code and its forks, such as Cursor.

This was our first step towards bringing IntelliJ IDEA’s Java and Kotlin intelligence beyond the IDE, giving developers and their agents accurate, project-aware code understanding across their tools and workflows.

We’re moving fast on that commitment, and today marks another big step: Java and Kotlin by IntelliJ IDEA has reached the Release Candidate stage. The foundation for a stable 1.0 release is now in place, and the release itself will arrive very soon.

This RC is the final Early Access Program build and will remain available under the EAP terms for 30 days.

If you’ve been waiting for the right moment to try the extension on a real project, this is it.

Install from Visual Studio Marketplace

Install from Open VSX registry

From preview to Release Candidate

Since the first public preview, we’ve shipped several intermediate builds, improving performance, reliability, and the extension’s feature set along the way.

The extension has now been downloaded over 20,000 times across Visual Studio Marketplace and Open VSX Registry.

Early adopters helped us get here by reporting issues, sharing projects and logs, and telling us which capabilities they wanted to see next. We’ve also been dogfooding the extension ourselves, including on the large repository used to build IntelliJ-based IDEs.

The RC brings IntelliJ IDEA’s Java and Kotlin language technology to the whole development workflow. Alongside IntelliJ IDEA’s core coding assistance – including smart code completion, navigation, inspections, quick-fixes, and code analysis – the extension provides more advanced capabilities, such as project-wide refactorings, DAP-based debugging, Maven, Gradle, and Bazel project support, built-in test running, Spring tooling interoperability, and more.

It also makes this intelligence available to coding agents. When the extension is installed in Cursor, Cursor Agent can use the same language server for semantic code search, navigation, and code analysis, leading to faster and more deterministic results.

We’re continuing to invest in this direction. The goal is not simply to reproduce IDE features in another editor. It is to make IntelliJ IDEA’s understanding of JVM code useful to developers and their tools wherever they choose to work.

Over the coming weeks, we’ll take a closer look at these capabilities and share more about where we’re taking the technology next, including fully agentic, terminal-based workflows.

What the Release Candidate means for licensing

The RC build is part of the Early Access Program and can be used for 30 days without a license.

Starting with the stable release, new users will receive a 30-day free trial. After the trial period, using the extension will require an IntelliJ IDEA Ultimate subscription.

Try the Release Candidate

Install Java and Kotlin by IntelliJ IDEA in VS Code, Cursor, or another compatible VS Code-based editor, open a real project, and tell us what you think.

You can leave a comment here or submit a request to us.

Thank you!

Get Java and Kotlin by IntelliJ IDEA from Visual Studio Marketplace

Get Java and Kotlin by IntelliJ IDEA from Open VSX Registry