@sylphlab/eslint-config-sylph

Strict, AI-optimized ESLint Flat Config for modern TypeScript. Extreme code quality, maintainability, and developer/AI efficiency. Core of all SylphLab TypeScript projects.

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Philosophy

• Strictest possible: All critical rules are errors. No compromise.
• Modern Flat Config: ESLint v9+, TypeScript 5+, ESM, Prettier 3+.
• AI & developer optimized: Explicit typing, clear naming, strict structure, Prettier formatting.
• Functional & secure: Immutability, no-throw, security, bug detection, complexity limits.
• Performance: Static analysis, code splitting, low complexity, short functions/files.

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Included Plugins

• @eslint/js (recommended)
• @typescript-eslint/eslint-plugin (strict, stylistic)
• eslint-plugin-unicorn
• eslint-plugin-functional
• eslint-plugin-security
• eslint-plugin-sonarjs
• eslint-plugin-promise
• eslint-plugin-regexp
• eslint-plugin-import-x
• eslint-config-prettier, eslint-plugin-prettier
• globals

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Install

1pnpm add -D @sylphlab/eslint-config-sylph eslint@^9 typescript@^5 prettier@^3
2npx install-peerdeps --dev @sylphlab/eslint-config-sylph -p pnpm

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Usage

Create eslint.config.ts:

1import sylphConfig from '@sylphlab/eslint-config-sylph';
2
3export default [
4  ...sylphConfig,
5  // project-specific overrides
6];

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Key Features

• Flat Config, ESM, type-safe
• Strictest rules:
  • No any, no unused, explicit return types, strict type imports/exports
  • Immutability, no-throw, no-mutable-exports, strict import order
  • Complexity, max-lines, max-lines-per-function, max-depth, max-params
  • Security, bug detection, promise handling, regex safety
• Functional programming:
  • Immutability, pure functions, no-throw, no-mixed-types
• Prettier enforced:
  • All formatting handled by Prettier, no conflicts
• AI/Developer ergonomics:
  • Explicit, predictable, easy for AI to refactor/extend

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Example: Override

1export default [
2  ...sylphConfig,
3  {
4    files: ['src/**/*.ts'],
5    rules: {
6      'no-console': 'off',
7      'unicorn/prevent-abbreviations': ['error', { replacements: { props: false, ref: false } }],
8    },
9  },
10  {
11    ignores: ['dist/', 'build/', 'coverage/', 'my-custom-ignored-folder/'],
12  },
13];

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See Also

• Monorepo README for full philosophy, structure, and all configs.