Comparing Biome and ESLint: A Comprehensive Guide

In 2025, JavaScript developers face a critical choice: stick with the battle-tested ESLint or embrace the speed of Biome. After extensive testing with both tools, here's everything you need to make an informed decision.

Performance Benchmarks: The Numbers Don't Lie

Biome's Rust-based architecture delivers impressive performance improvements:

• Formatting: 25x faster than Prettier
• Linting: 15x faster than ESLint
• Cold starts: 3-5x improvement in CI/CD pipelines

In real-world testing on a medium-sized TypeScript project (50K lines):

• ESLint: 15 seconds with full type-checking
• Biome: 6 seconds with type-aware rules

Installing Biome in a Next.js Project

Let's walk through setting up Biome in a Next.js application:

This creates a biome.json configuration file:

Update package.json Scripts

Migrating from ESLint and Prettier

Biome provides an automated migration command:

Manual Migration Steps

For a complete migration:

1. Remove ESLint and Prettier dependencies

1. Delete configuration files

1. Update VS Code settings (.vscode/settings.json)

Setting Up Biome in a React Project

For Create React App or Vite projects:

CI/CD Integration

Add Biome to your CI pipeline for consistent code quality:

When to Choose Biome vs ESLint

Choose Biome if:

• Speed is critical (fast CI/CD pipelines)
• You want an all-in-one tool (linter + formatter)
• Starting a new project without legacy constraints
• You value simple configuration

Choose ESLint if:

• You need specific plugins (e.g., testing-library, jest)
• Large existing codebase with custom ESLint rules
• Team already invested in ESLint ecosystem
• Need maximum rule customization

Real-World Migration Experience

After migrating three production projects to Biome:

• CI pipeline time reduced by 40%
• Developer feedback loop improved significantly
• Configuration complexity decreased dramatically
• Zero compatibility issues with modern tooling

Biome represents the future of JavaScript tooling - faster, simpler, and more reliable. For new projects in 2025, it's the clear choice. For existing projects, the migration path is straightforward and the benefits are immediate.