# Lit

Lit is a simple library for building fast, lightweight web components.

Repository: https://github.com/lit/lit
Canonical: https://ross.abutalabs.com/products/lit
Homepage: https://lit.dev
Language: TypeScript
License: BSD-3-Clause
License Family: permissive
Topics: lit-html, lit-element, html-templates, lit
Last push: 2026-07-25T18:36:25+00:00
Link (homepage): https://lit.dev
Link (site_page): https://lit.dev/docs
Link (site_page): https://lit.dev/docs/getting-started
Link (site_page): https://lit.dev/discord

## Health v2 (maintenance only)
Score: 92/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 94, release rhythm 84, longevity 100
- inputs: {"age_days": 3352, "days_push": 39, "days_rel": 111, "gap_med": 0, "n_releases_24m": 52}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 21788, forks 1094 (observed 2026-08-28T04:11:32.087271+00:00)

## What it is
Lit is a small (~5 KB) TypeScript library for building fast, lightweight web components on top of browser standards. It provides a reactive base class, scoped styles, and an efficient declarative HTML template system (lit-html) that only updates dynamic DOM parts.

## Use cases
- build reusable web components
- create a design system usable across frameworks
- build a fast lightweight single-page app without a heavy framework
- progressively enhance server-rendered or CMS-driven HTML pages
- share components between React, Vue, and plain HTML apps
- add interactivity to static sites built with Jekyll or eleventy

## When to choose
- you want framework-agnostic components that work anywhere HTML works
- bundle size and rendering performance are priorities
- you're building a shareable component library or design system
- you want minimal lock-in and easy incremental migration

## When to avoid
- you need a large ecosystem with batteries-included routing, state, and data layers
- your team is already deeply invested in React or Vue conventions
- you need mature SSR out of the box (Lit SSR is still in labs)
- you require extensive mobile-native support

## Facets
- artifact type: library
- maturity: stable
- function: frontend-framework, ui-components, templating, state-management
- domain: web-development, frontend, web-design
- platform: browser, cross-platform
- tags: web-components, lit-html, lit-element, custom-elements, shadow-dom, design-systems, typescript, web-server, nodejs

## Member repositories
- lit/lit (main) score 92
- lit/lit-element (mirror) score 63

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:32.087271+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:57:48.233154+00:00, confidence not recorded.
  - readme: https://github.com/lit/lit (fetched 2026-08-28T04:11:32.087271+00:00, sha dd44bb4dde39)
  - homepage: https://lit.dev (fetched 2026-08-29T07:56:59.738737+00:00, sha d7d3b65df1eb)
  - site_page: https://lit.dev/docs (fetched 2026-08-29T07:56:59.743569+00:00, sha d59b8fb5c0e4)
  - site_page: https://lit.dev/docs/getting-started (fetched 2026-08-29T07:56:59.746031+00:00, sha 15d3a512fac8)
  - registry_npm: https://registry.npmjs.org/lit (fetched 2026-08-29T07:56:59.750480+00:00, sha 12e31e3f56d0)
  - site_page: https://lit.dev/discord (fetched 2026-08-29T07:56:59.748482+00:00, sha 7e8821263393)
- Data as of 2026-08-30T08:39:29.467469+00:00.