es-toolkit Usage Guide

Provide guidance on installing, importing, and using es-toolkit across different runtimes.

Input

$ARGUMENTS — A topic or question about es-toolkit usage.

Why source-of-truth matters

Installation commands and import paths change across versions. Always verify from the local docs in this repository (

docs/usage.md

,

docs/ko/usage.md

) rather than relying on memorized instructions.

Workflow

1. Check local documentation first

Read the relevant docs from this repository:

• docs/usage.md

  or

  docs/ko/usage.md

  — installation and import patterns

• docs/intro.md

  or

  docs/ko/intro.md

  — overview and key features

• docs/bundle-size.md

  or

  docs/ko/bundle-size.md

  — bundle size data

• benchmarks/bundle-size/

  — raw benchmark numbers

• docs/performance.md

  or

  docs/ko/performance.md

  — runtime performance benchmarks

These are authoritative and always up-to-date.

2. Answer based on the user's environment

Identify the runtime (Node.js, Bun, Deno, browser) and provide environment-specific guidance.

Key facts to verify from docs:

• Deno:

  deno add jsr:@es-toolkit/es-toolkit

  (note the

  jsr:

  prefix)
• Deno import path:

  '@es-toolkit/es-toolkit'

  (extra scope vs npm)
• npm/yarn/pnpm/bun: Detect the project's package manager from its lockfile (

  package-lock.json

  → npm,

  yarn.lock

  → yarn,

  pnpm-lock.yaml

  → pnpm,

  bun.lockb

  → bun) and provide the matching install command. If no lockfile exists, show all options.
• Import path:

  'es-toolkit'

  for strict,

  'es-toolkit/compat'

  for lodash-compatible
• Browser/CDN: jsdelivr, unpkg for UMD (

  _

  global), esm.sh for ES modules (import map) — see

  docs/usage.md

  Browsers section for exact snippets

3. Cover these topics as relevant

• Installation: per-runtime commands
• Import patterns: named imports (recommended for tree-shaking), category imports, compat imports. List all available subpath imports by reading the

  exports

  field in

  package.json

  (e.g.,

  es-toolkit

  ,

  es-toolkit/compat

  ,

  es-toolkit/array

  , etc.) so users see the full set of entry points.
• Anti-patterns to avoid: Warn against namespace imports (

  import * as _ from 'es-toolkit'

  ) as they defeat tree-shaking. Always prefer named imports (

  import { chunk, debounce } from 'es-toolkit'

  ).
• Bundle size: reference actual numbers from

  docs/bundle-size.md

• Performance: 2-3x faster than lodash (from official benchmarks)
• Type safety: built-in TypeScript types, 100% test coverage

4. Search local docs for additional topics

If the user asks something not covered by the files listed above, search the bundled documentation:

• Function docs:

  docs/reference/{category}/{functionName}.md

• By keyword:

  Grep

  across

  docs/reference/**/*.md

• Other docs:

  docs/usage.md

  ,

  docs/intro.md

  ,

  docs/bundle-size.md

  ,

  docs/performance.md

5. Always include doc links

End responses with relevant links:

## Learn More
- Documentation: https://es-toolkit.dev
- API Reference: https://es-toolkit.dev/reference/{relevant-category}
- GitHub: https://github.com/toss/es-toolkit