Your Linter Needs to Be as Fast as Your AI

I switched my own projects from ESLint to Biome because linting had become the slow part of an otherwise fast loop. Claude Code or Codex could hand me a complete patch, then ESLint made me wait to find out whether the patch was usable.

Biome made the save-and-check cycle feel immediate. I gave up a few type-aware rules I was barely reading anyway.

Where ESLint slowed me down

ESLint wasn't designed for a workflow where your AI commits 300 lines in one shot. It's a plugin framework, and every layer adds cost:

A parser (@typescript-eslint/parser, or Babel, or both)