The monorepo for Lit packages, including lit, lit-html and LitElement.

To learn more and get started using Lit, check out the About Lit 2.0. For information about upgrading lit-html 1.x and lit-element 2.x code, see Lit 2.0 Upgrade Guide.

• Core packages
  • lit - The primary user-facing package of Lit which includes everything from lit-html and lit-element.
  • lit-element - The web component base class used in Lit.
  • lit-html - The rendering library used by LitElement.
  • @lit/reactive-element - A low level base class that provides a reactive lifecycle based on attribute/property changes.
• Additional libraries
  • @lit/localize - A library and command-line tool for localizing web applications built using Lit.
• Labs
  • @lit/localize-tools - Localization tooling for use with @lit/localize.
• Labs
  • @lit-labs/ssr - A server package for rendering Lit templates and components on the server.
  • @lit-labs/ssr-cient - A set of client-side support modules for rendering Lit components and templates on the server using @lit-labs/ssr.
  • @lit-labs/react - A React component wrapper for web components.
  • @lit-labs/task - A controller for Lit that renders asynchronous tasks.
  • @lit-labs/scoped-registry-mixin - A mixin for LitElement that integrates with the speculative Scoped CustomElementRegistry polyfill.
• Starter kits (not published to npm)
  • lit-starter-ts (template repo) - A starter repo for building reusable components using Lit in TypeScript.
  • lit-starter-js (template repo) - A starter repo for building reusable components using Lit in Javascript.
• Internal packages (not published to npm)
  • tests - Test infrastructure for the monorepo.
  • benchmarks - Benchmarks for testing various libraries in the monorepo.
  • internal-scripts - Utility scripts used within the monorepo.

Lit is open source and we appreciate issue reports and pull requests. See CONTRIBUTING.md for more information.

Initialize repo:

git clone https://github.com/Polymer/lit-html.git -b lit-next
cd lit-html
npm install
npm run bootstrap

Build all packages:

npm run build

Test all packages:

npm run test

Run benchmarks for all packages:

npm run benchmarks

See individual package READMEs for details on developing for a specific package.

Although we maintain lit-starter-ts and lit-starter-js in the monorepo for ease of integration testing, the source is exported back out to individual repos (ts, js) as these are GitHub Template Repositories with a nice workflow for users to create their own new element repos based on the template.

Use the following command to export new commits to the monorepo packages to a branch on the template repos (lit-next branch shown in example):

# Export TS template
git remote add lit-element-starter-ts git@github.com:PolymerLabs/lit-element-starter-ts.git
git subtree push --prefix=packages/lit-starter-ts/ lit-starter-element-ts lit-next

# Export JS template
git remote add lit-element-starter-js git@github.com:PolymerLabs/lit-starter-js.git
git subtree push --prefix=packages/lit-starter-js/ lit-starter-element-js lit-next

Notes:

• If your version of git did not come with git-subtree, you can add it by cloning the git source at git@github.com:git/git.git and symlinking git/contrib/subtree/git-subtree into your path (e.g. /usr/local/bin)
• If git subtree errors with a segmentation fault, try increasing your stack size prior to running, e.g. ulimit -s 16384