@antelopejs/tooling-configs

Shared tooling presets for AntelopeJS repositories: oxlint (including the vendored anti-slop rules), oxfmt and Knip.

Together they replace Biome outright — lint, format and import order — and Prettier in the Nuxt layers, since oxfmt formats .vue and sorts Tailwind classes natively. The front end keeps ESLint for linting, from a shared config here.

Requirements

Node 24 (or at least 22.18). oxlint reads oxlint.config.ts and loads JS plugins by executing TypeScript, which earlier runtimes cannot do.

Install

pnpm add -D [email protected] oxfmt @antelopejs/tooling-configs

Add eslint-plugin-perfectionist too unless you turn import sorting off — it is an optional peer dependency because it pulls ESLint and typescript-eslint along with it:

pnpm add -D eslint-plugin-perfectionist

Pin oxlint to the exact version this package depends on for @oxlint/plugins (currently 1.81.0). The JS plugin API is still alpha and the two packages must move together.

oxlint

// oxlint.config.ts
import { defineConfig } from "oxlint";
import { antelopePreset } from "@antelopejs/tooling-configs/oxc/lint";

export default defineConfig({
  extends: [antelopePreset()],
  // Only read from the root config, never from a preset.
  options: { typeAware: true },
});

// package.json
{
  "scripts": {
    "lint": "oxlint",
    "lint:fix": "oxlint --fix",
  },
}

Type-aware rules (typescript/no-floating-promises) also need the tsgolint binary:

pnpm add -D oxlint-tsgolint

What the preset turns on

| Group | Contents | | -------------- | ----------------------------------------------------------------------------------------------------------- | | oxc defaults | the correctness category, plus the eslint, typescript, node, oxc, import and promise plugins | | imports | import/no-cycle, import/no-self-import, import/no-duplicates as errors | | | (a repository with existing cycles starts with importCycles: "warn") | | import sorting | perfectionist/sort-imports, autofixed by oxlint --fix | | complexity | max-params 5, max-lines-per-function 120, max-lines 500, max-depth 4, complexity 20 — as warnings | | anti-slop | all 15 generic rules, as warnings | | type-aware | typescript/no-floating-promises as an error |

Options

antelopePreset({
  antiSlop: "error", // "warn" (default) | "error" | false
  importCycles: "warn", // "error" (default) | "warn" | false
  complexity: { maxParams: 8 }, // override thresholds, or false
  importSorting: false, // leave imports alone
  typeAware: false, // no tsgolint in this repository
});

correctness is raised to error deliberately. oxlint reports it as warnings, and warnings do not fail the command — a preset that left it alone could never fail a pipeline, while Biome was failing the build on the same rules.

antiSlop and complexity default to warnings on purpose: a repository adopting them has findings to work through, and a red pipeline on day one teaches the team to ignore the pipeline. Raise them to "error" once the backlog is clear.

Adding your own ignore patterns

oxlint does not merge ignorePatterns across extends. A root config that declares its own replaces the preset's, so spread them:

import {
  ANTELOPE_IGNORE_PATTERNS,
  antelopePreset,
} from "@antelopejs/tooling-configs/oxc/lint";

export default defineConfig({
  extends: [antelopePreset()],
  ignorePatterns: [...ANTELOPE_IGNORE_PATTERNS, "playground/**"],
});

oxfmt

// oxfmt.config.ts
import { antelopeFmtPreset } from "@antelopejs/tooling-configs/oxc/fmt";

export default antelopeFmtPreset();

// package.json
{
  "scripts": {
    "format": "oxfmt .",
    "format:check": "oxfmt --check .",
  },
}

The house style

| Option | Value | | ---------------------- | ---------- | | printWidth | 80 | | tabWidth / useTabs | 2 / spaces | | semi | true | | singleQuote | false | | trailingComma | "all" |

Every field is set explicitly, including those that already match oxfmt's defaults. Repositories carry .editorconfig files that contradict each other — five declare tabs, two declare spaces, which is why the codebases drifted apart in the first place — and oxfmt falls back to .editorconfig for any field a config leaves unset. Stating all of them is what makes the style identical everywhere. Fix the repository's .editorconfig to match anyway, so editors agree with the formatter.

Import order is not part of it: perfectionist/sort-imports owns that on the lint side. Enabling oxfmt's sortImports as well would have two tools sorting the same imports differently, each undoing the other on every save.

Extra ignores are added to the shared ones rather than replacing them, so a repository adopting oxfmt in stages can park a directory without losing the rest:

export default antelopeFmtPreset({ ignorePatterns: ["frontend-vue/**"] });

In a front end, pass the theme stylesheet to replace prettier-plugin-tailwindcss:

export default antelopeFmtPreset({
  tailwindStylesheet: "./assets/css/main.css",
});

Replacing Biome

Per repository: delete biome.json and the @biomejs/biome dependency, point lint, lint:fix and format at oxlint and oxfmt, and port anything the Biome config carried that the preset does not (noRestrictedImports guards become import/no-cycle). Reformat in its own commit and record it in .git-blame-ignore-revs, which GitHub honours, so the pass does not bury the history.

ESLint (front ends)

oxlint does not lint .vue files yet, so the front end stays on ESLint:

// frontend-vue/eslint.config.mjs
import { antelopeNuxtConfig } from "@antelopejs/tooling-configs/eslint";

export default antelopeNuxtConfig({ dirs: ["./playground"] });

@nuxt/eslint supplies the Vue and TypeScript rules; the preset only records where AntelopeJS layers differ from it — single-word page components, any and {} as load-bearing types in the interface layer, _-prefixed unused bindings, and import order left to the formatter.

Formatting rules are deliberately absent, vue/max-attributes-per-line included: oxfmt formats .vue, and a lint rule that also reflows markup would fight it on every save. Declare @nuxt/eslint-config explicitly — nine layers use it today through @nuxt/eslint without declaring it.

Knip

// knip.config.ts
import { antelopeKnipConfig } from "@antelopejs/tooling-configs/knip";

export default antelopeKnipConfig();

The defaults declare what Knip cannot infer for an AntelopeJS module: the interface subpaths as public API, and src/test/** plus a root antelope.test.ts as entry points, since ajs module test is not a runner Knip has a plugin for. Without them, Knip reports the whole test suite as dead code.

src/index.ts is not among them on purpose: Knip already maps the main/bin of package.json (dist/index.js) back onto src/index.ts, ahead of the dist/** ignore, so repeating it only earns a "redundant pattern" hint.

The front end is left out of project rather than ignored, so a repository that wants frontend-vue/ analysed can add it under Knip's workspaces without the preset overriding the choice.

Vendored anti-slop

src/oxc/anti-slop/ is a copy of upstream, kept byte-identical so it can be diffed against new releases. See src/oxc/anti-slop/VENDORED.md for the commit it came from and any local edits. It is excluded from this repository's own formatting and linting.

Upstream is MIT (src/oxc/anti-slop/LICENSE); the rest of this repository is Apache-2.0.