ESLint 10 looks up eslint.config.* from each linted file's directory, not the cwd — affects monorepos

• Remove the old flag everywhere: --flag v10_config_lookup_from_file on the CLI, the ESLINT_FLAGS env var, and the flags array passed to new ESLint() / new Linter() (npx codemod @eslint/v9-to-v10 does this).
• If you want one config for the whole repo (old cwd-based behaviour), pass it explicitly:

npx eslint --config ./eslint.config.js .

• Otherwise, make sure each package's eslint.config.js is complete on its own (it no longer inherits anything from the root unless it imports it):

// packages/web/eslint.config.js
import { defineConfig } from 'eslint/config'
import root from '../../eslint.config.js'
export default defineConfig([root, { rules: { 'no-console': 'off' } }])

Also required for v10: Node.js 20.19+, 22.13+ or 24+ (Node < 20.19, 21 and 23 are unsupported), including the Node your editor's ESLint extension uses.