@vllnt/eslint-config

Strict, opinionated ESLint flat config for TypeScript projects. Every rule enforces error — no warnings, no compromises.

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Why

• ESLint v9+ flat config only — no legacy .eslintrc
• TypeScript-first with strictTypeChecked + stylisticTypeChecked
• Prettier built-in — formatting as lint errors, zero config
• 7 presets — Base, React, Next.js, Node.js, Convex, Turbo, Boundaries
• Composable — spread arrays, override anything

Install

pnpm add -D @vllnt/eslint-config eslint typescript prettier

Quick start

// eslint.config.js
import { nextjs } from '@vllnt/eslint-config/nextjs'

export default [...nextjs]

Each preset is an array — spread it into your flat config. All presets include projectService: true for type-aware linting.

Presets

Import	Use case
@vllnt/eslint-config	Base — TypeScript strict + Prettier + import sorting
@vllnt/eslint-config/nextjs	Next.js apps (includes React + a11y + core web vitals)
@vllnt/eslint-config/react	React apps without Next.js
@vllnt/eslint-config/nodejs	Node.js backends
@vllnt/eslint-config/convex	Convex backends (4 official + 7 custom rules)
@vllnt/eslint-config/turbo	Turborepo cache rules (opt-in)
@vllnt/eslint-config/boundaries	Architecture boundary enforcement (opt-in)

Composing presets

Mix and match — presets are arrays:

import { nodejs } from '@vllnt/eslint-config/nodejs'
import { turbo } from '@vllnt/eslint-config/turbo'

export default [...nodejs, ...turbo]

Override any rule by appending a config object:

import { nodejs } from '@vllnt/eslint-config/nodejs'

export default [
  ...nodejs,
  {
    rules: {
      'max-lines-per-function': ['error', { max: 50 }],
    },
  },
]

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What's included

Base (all presets)

Plugin	What it does
@eslint/js	ESLint recommended rules
typescript-eslint	strictTypeChecked + stylisticTypeChecked
eslint-plugin-prettier	Prettier as ESLint errors
eslint-config-prettier	Disables conflicting rules
eslint-plugin-perfectionist	Import/object/type sorting
eslint-plugin-unicorn	Modern JS best practices
eslint-plugin-simple-import-sort	Import ordering
eslint-plugin-functional	Functional patterns (no loops, readonly)
eslint-plugin-write-good-comments	Comment quality

Plus: strict naming conventions (camelCase, PascalCase types, T-prefixed generics), no enums (union types enforced via AST selector).

React additions

Plugin	What it does
eslint-plugin-react	Recommended + jsx-runtime
eslint-plugin-react-hooks	Rules of hooks
eslint-plugin-jsx-a11y	Accessibility
eslint-plugin-css-modules	CSS module validation

Next.js additions

Everything in React, plus:

Plugin	What it does
@next/eslint-plugin-next	Recommended + core web vitals (all error)

Route handler method restrictions, page/layout max-lines-per-function override.

Opt-in

Preset	Plugin
Turbo	eslint-plugin-turbo cache rules
Boundaries	eslint-plugin-boundaries architecture enforcement

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Convex preset

The Convex preset enforces backend best practices with 4 official rules + 7 custom rules bundled as eslint-plugin-convex-rules.

Setup

// Standalone
import { convex } from '@vllnt/eslint-config/convex'

export default [...convex]

// With base (recommended)
import { base } from '@vllnt/eslint-config'
import { convex } from '@vllnt/eslint-config/convex'

export default [...base, ...convex]

Official rules (@convex-dev)

Rule	Catches
no-old-registered-function-syntax	Deprecated function syntax
require-args-validator	Missing args validator
explicit-table-ids	Implicit table ID types
import-wrong-runtime	Wrong runtime imports (Node in Convex runtime)

Custom rules (convex-rules)

Rule	Catches
standard-filenames	Factories outside queries.ts, mutations.ts, actions.ts
namespace-separation	query() in mutations.ts, mutation() in queries.ts
snake-case-filenames	Hyphens in convex/ filenames (must be snake_case)
no-bare-v-any	v.any() outside validators.ts
require-returns-validator	Missing returns validator in factory config
no-query-in-loop	N+1 queries (ctx.db.query/get/runQuery inside loops)
no-filter-on-query	.filter() on query chains (use .withIndex())

Auto-applied overrides

• Config files (auth.ts, auth.config.ts, convex.config.ts) — exempt from snake-case-filenames and explicit-module-boundary-types
• Migration files (convex/migrations/**) — exempt from standard-filenames, namespace-separation, no-query-in-loop
• Generated/test files (convex/_generated/**, *.test.ts, convex/testing/**) — excluded entirely

Project-specific overrides

import { base } from '@vllnt/eslint-config'
import { convex } from '@vllnt/eslint-config/convex'

export default [
  ...base,
  ...convex,

  // Exempt "use node" action files from import-wrong-runtime
  {
    files: ['convex/agents/actions.ts'],
    rules: { '@convex-dev/import-wrong-runtime': 'off' },
  },
]

Enforced file structure

convex/
  {domain}/
    queries.ts              query(), internalQuery()
    mutations.ts            mutation(), internalMutation()
    actions.ts              action(), internalAction()
    internal_mutations.ts   internalMutation() (optional split)
    validators.ts           v.* validators + types
    schema.ts               table definitions
  lib/
    validators.ts           shared v.any() aliases
  _generated/               auto-generated (excluded)
  migrations/               relaxed rules

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Peer dependencies

Package	Required
eslint >= 9	Yes
prettier >= 3	Yes
typescript >= 5	Optional

VS Code

Add to .vscode/settings.json for monorepo support:

{
  "eslint.workingDirectories": [
    "./apps/your-app",
    "./packages/your-package"
  ]
}

License

MIT