configure-linting-for-effect

description: Use Biome for fast linting with Effect-friendly configuration. globs: "**/*.ts" alwaysApply: true

Configure Linting for Effect

Rule: Use Biome for fast linting with Effect-friendly configuration.

Example

1. Biome Configuration (Recommended)

// biome.json
{
  "$schema": "https://biomejs.dev/schemas/1.8.0/schema.json",
  "organizeImports": {
    "enabled": true
  },
  "linter": {
    "enabled": true,
    "rules": {
      "recommended": true,
      "complexity": {
        "noExcessiveCognitiveComplexity": "warn",
        "noForEach": "off",  // Effect uses forEach patterns
        "useLiteralKeys": "off"  // Effect uses computed keys
      },
      "correctness": {
        "noUnusedVariables": "error",
        "noUnusedImports": "error",
        "useExhaustiveDependencies": "warn"
      },
      "style": {
        "noNonNullAssertion": "warn",
        "useConst": "error",
        "noParameterAssign": "error"
      },
      "suspicious": {
        "noExplicitAny": "warn",
        "noConfusingVoidType": "off"  // Effect uses void
      },
      "nursery": {
        "noRestrictedImports": {
          "level": "error",
          "options": {
            "paths": {
              "lodash": "Use Effect functions instead",
              "ramda": "Use Effect functions instead"
            }
          }
        }
      }
    }
  },
  "formatter": {
    "enabled": true,
    "indentStyle": "space",
    "indentWidth": 2,
    "lineWidth": 100
  },
  "javascript": {
    "formatter": {
      "semicolons": "asNeeded",
      "quoteStyle": "double",
      "trailingComma": "es5"
    }
  },
  "files": {
    "ignore": [
      "node_modules",
      "dist",
      "coverage",
      "*.gen.ts"
    ]
  }
}

2. ESLint Configuration (Alternative)

// eslint.config.js
import eslint from "@eslint/js"
import tseslint from "typescript-eslint"

export default tseslint.config(
  eslint.configs.recommended,
  ...tseslint.configs.strictTypeChecked,
  {
    languageOptions: {
      parserOptions: {
        project: true,
        tsconfigRootDir: import.meta.dirname,
      },
    },
    rules: {
      // TypeScript strict rules
      "@typescript-eslint/no-unused-vars": [
        "error",
        { argsIgnorePattern: "^_" }
      ],
      "@typescript-eslint/no-explicit-any": "warn",
      "@typescript-eslint/explicit-function-return-type": "off",
      "@typescript-eslint/no-floating-promises": "error",

      // Effect-friendly rules
      "@typescript-eslint/no-confusing-void-expression": "off",
      "@typescript-eslint/no-misused-promises": [
        "error",
        { checksVoidReturn: false }
      ],

      // Style rules
      "prefer-const": "error",
      "no-var": "error",
      "object-shorthand": "error",
      "prefer-template": "error",
    },
  },
  {
    files: ["**/*.test.ts"],
    rules: {
      "@typescript-eslint/no-explicit-any": "off",
    },
  },
  {
    ignores: ["dist/", "coverage/", "node_modules/"],
  }
)