ESLint Rspack Plugin Goes ESM-Only: What It Means for Developer Communities

Introduction: A New Era for ESLint in Rspack

The online developer community is abuzz with the latest release of eslint-rspack-plugin, version 5.0.0. This update marks a significant shift towards a pure ESM (ECMAScript Module) package, aligning with the broader Rstack ecosystem's modernization efforts. For developers who rely on Rspack for their build processes, this change brings both opportunities and considerations.

In this article, we'll explore the implications of this release for online communities of developers, focusing on how the shift to ESM-only packages affects collaboration, code sharing, and build performance. We'll also delve into the community's evolving best practices around linting and the growing popularity of faster alternatives like Rslint.

The Pure ESM Transition: A Community-Wide Shift

The move to pure ESM in eslint-rspack-plugin mirrors Rspack 2.0's decision to drop CommonJS builds. This transition is part of a broader trend in the JavaScript ecosystem towards modern module systems. For online communities, this means that shared code and plugins are increasingly ESM-only, which can impact how developers configure their projects.

However, the good news is that Node.js 20 and later versions support require(esm), allowing most projects to use the plugin via JavaScript API without any code changes. This compatibility reduces friction for community members, ensuring that the transition is mostly seamless.

What's New in Version 5.0.0?

Version 5.0.0 brings several key features that are particularly relevant to community-driven projects:

• Cache by default: The plugin now enables caching by default, which can significantly reduce execution time during builds.
• configType option: This allows developers to switch between the classic eslintrc format and the new flat config, offering flexibility for teams with different preferences.
• Threads support: Linting tasks can be run in a thread pool, improving performance on multi-core systems.
• lintAllFiles option: This ensures that all matching files are linted, not just those in the dependency graph. This is particularly useful in multi-environment builds (e.g., Rsbuild and Rspack) where separate client and server checks might miss files.

These features are designed to enhance the developer experience and streamline workflows, which are central to thriving online communities.

Performance Considerations: Lint Outside the Build?

The plugin's README includes a notable caution: running ESLint during the build process can increase build times. It suggests that using a separate linting command might be more efficient. This advice is echoed in the Rsbuild FAQ, which states that Rsbuild does not run ESLint during builds by default to preserve compilation performance.

This guidance reflects a growing consensus in the developer community: separating linting from the build process can lead to faster builds and more focused tooling. For online communities that share build configurations and best practices, this is an important consideration to discuss and adopt.

The Rise of Rslint: A Game Changer for Community Tooling

In line with this shift, the Rstack team has introduced Rslint, a TypeScript-first, ESLint-compatible linter written in Go, based on typescript-go. Rslint claims to be 20 to 40 times faster than traditional ESLint configurations. This has sparked excitement in online communities, as faster tooling means quicker feedback loops and more efficient collaboration.

For teams that prioritize build speed, using a standalone fast linter—whether through a dedicated script or an alternative like Rslint—is becoming more attractive than integrating linting into the bundler. This trend is likely to influence how community projects structure their development pipelines.

Upgrading from 4.x: What Developers Need to Know

Developers upgrading from the 4.x series should test the pure ESM changes in their toolchains and consider adopting ESLint's flat config via configType: 'flat' where feasible. The Rspack 2.0 release notes provide additional context on the underlying ESM migration.

Online communities can play a vital role in easing this transition by sharing migration experiences, troubleshooting tips, and updated configuration examples. Collaborative knowledge sharing is essential for smooth upgrades across projects.

Conclusion: Embracing Change in Developer Communities

The eslint-rspack-plugin 5.0.0 release is more than just a version bump; it's a reflection of the evolving landscape of JavaScript tooling. For online communities, staying informed and adapting to these changes is crucial. The shift to pure ESM, the emphasis on build performance, and the emergence of faster alternatives like Rslint are all trends that will shape the future of web development.

As we embrace these changes, let's continue to foster open discussions, share insights, and support each other in our development journeys. The strength of our communities lies in our collective ability to adapt and innovate.