@doubleloop-io/oxlint-plugin-effect

An oxlint plugin that enforces a catalog of patterns for Effect 4 code.

The rules are written and tested against Effect 4. Where an Effect 3 API has the same intent, the rules recognize its v3 name too: each rule's Trigger names them. The Rules overview lists every rule.

It complements the type-aware rules of @effect/tsgo: it does not need them, and it checks what they do not.

Installation

pnpm add -D @doubleloop-io/oxlint-plugin-effect oxlint

Requires Node ^22.20.0 || >=24.8.0 and oxlint ^1.82.0. What a release may change and which oxlint versions are supported: Versioning.

Usage

Extend the all preset. Prefer oxlint.config.ts, where extends takes config objects and the preset is imported by package name:

import dlEffectAll from "@doubleloop-io/oxlint-plugin-effect/presets/all"
import { defineConfig } from "oxlint"

export default defineConfig({ extends: [dlEffectAll] })

With .oxlintrc.json, extends takes file paths only, so the preset is reached through node_modules:

{
    "extends": ["./node_modules/@doubleloop-io/oxlint-plugin-effect/dist/presets/all.json"]
}

all enables every rule at warn, so adopting it never breaks a build: look at the warnings first, then raise to error the rules you want to enforce.

Set entryFiles before reading the warnings on a layout that is not a Node CLI, such as Next.js or a monorepo. Its default, **/main.ts, **/cli.ts, **/bin/**, decides which files may run Effects and import adapters, so on another layout it turns correct code into warnings. How to set it: Shared settings.

Documentation

The guide is on the website:

• Configuration: the all preset and picking rules.
• Shared settings: the settings that describe your project, their defaults and the rules that use them.
• Default configuration: all with every setting and option spelled out.
• Alongside @effect/tsgo: combining its presets with this one.
• Rules overview: every rule, grouped by topic.
• Versioning: what a release may change.
• Troubleshooting: the problems most often hit when adopting the plugin.

Coding agents: the same pages ship in the package under docs/user-guide/, starting from docs/user-guide/README.md.