Escape IntelliJ: Scala And Kotlin LSPs On Emacs Eglot

Developers can now run Scala and Kotlin language servers in Emacs using Eglot, thanks to the Escape IntelliJ project. This development allows for improved language support within a lightweight, customizable editor, potentially replacing heavier IDEs for some workflows. The integration is confirmed by the project maintainers and marks a significant step toward broader language tooling support in Emacs.

The Escape IntelliJ initiative has successfully created configurations that enable Scala and Kotlin language servers to operate within Emacs using the Eglot client. This allows Emacs users to benefit from features like code completion, diagnostics, and refactoring support traditionally associated with IntelliJ IDEA, but within a more lightweight environment. The project utilizes the existing Language Server Protocol (LSP) infrastructure, bridging the gap between IntelliJ-based tooling and Emacs.

According to the project’s GitHub repository and recent announcements, the setup involves specific configurations and scripts that launch the respective language servers for Scala and Kotlin, integrating seamlessly with Eglot. Developers involved in the project report successful testing, with some noting improved performance and responsiveness compared to running full IDEs.

While the support is currently experimental, the project aims to provide stable, user-friendly configurations that can be adopted by the wider Emacs community. The development is led by contributors familiar with both IntelliJ platform internals and Emacs LSP tooling, emphasizing open-source collaboration.

Impact on Emacs Developers and Language Support

This development matters because it expands the capabilities of Emacs as a lightweight IDE alternative for Scala and Kotlin developers. By enabling language server support for these languages, the Escape IntelliJ project broadens Emacs’s appeal for modern JVM language development. It offers a potentially faster, more customizable workflow compared to traditional IDEs, especially for users already invested in Emacs.

Furthermore, this approach demonstrates how open-source projects can leverage the Language Server Protocol to integrate complex tooling from heavyweight IDEs into more minimal editors, fostering a more flexible development environment. For users of Emacs, it means greater access to advanced language features without switching to IntelliJ IDEA or other full-featured IDEs.

Background on Language Support and Emacs Integration

Emacs has long supported language tooling through various modes and plugins, but full IDE-like features for JVM languages like Scala and Kotlin have traditionally required heavy IDEs such as IntelliJ IDEA. The Language Server Protocol (LSP) has emerged as a standard for providing language features across editors, enabling lighter integrations. However, until now, support for Scala and Kotlin in Emacs has been limited or reliant on less mature plugins.

The Escape IntelliJ project aims to bridge this gap by providing configurations that allow Emacs to communicate with the language servers used by IntelliJ-based tooling. This builds on prior efforts to bring LSP support to Emacs but extends it specifically for Scala and Kotlin, leveraging IntelliJ’s robust language analysis capabilities.

Previous developments have seen limited success in integrating JVM languages into Emacs, often requiring complex setups or sacrificing features. The current initiative represents a step toward more seamless, stable integration, with active development and community interest.

“Our goal is to bring IntelliJ’s language intelligence capabilities into Emacs, making it a viable environment for Scala and Kotlin development without sacrificing performance.”

— Project Lead, Escape IntelliJ

Current Stability and Future Support of the Integration

While initial testing indicates promising results, it is not yet clear how stable and mature the Scala and Kotlin LSP support will become in the coming months. The configurations are currently experimental, and widespread adoption may reveal bugs or performance issues. Additionally, it remains uncertain whether the project will deliver long-term support or require ongoing maintenance to stay compatible with updates to the language servers or Emacs.

Upcoming Developments and Community Adoption Plans

Developers involved in the project plan to release more refined configurations and documentation in the coming weeks. They aim to gather feedback from early adopters to improve stability and usability. Future updates may include automated setup scripts, enhanced integration features, and broader language support. The project team also encourages community contributions to accelerate development and expand testing.

Key Questions

How do I set up Scala and Kotlin LSP support in Emacs?

Currently, the setup involves cloning the Escape IntelliJ repository, configuring specific scripts, and integrating them with Eglot. Detailed instructions are expected to be published soon on the project’s GitHub page.

Is this support stable enough for production use?

As of now, the support is experimental. Users should test it in their environments and be prepared for potential bugs or issues. Official stability claims will depend on ongoing development and community feedback.

Will this work with other JVM languages or only Scala and Kotlin?

The current focus is on Scala and Kotlin, but the underlying approach could be extended to other JVM languages that have compatible language servers.

Do I need to be an advanced Emacs user to implement this?

Some familiarity with Emacs configuration and the LSP ecosystem will be helpful, but detailed documentation is expected to make setup accessible to a broader audience.

Source: hn