Sucrase
Sucrase is a free JavaScript transform tool for development builds aimed at modern runtimes.
What Sucrase is
Sucrase is a free JavaScript transform tool for development builds aimed at modern runtimes. It handles JSX, TypeScript, Flow, imports, React hot loader code, and Jest transforms, as well as syntax such as optional chaining, nullish coalescing, class fields, numeric separators, and optional catch binding. It can be installed as an npm or Yarn development dependency and used through a CLI, Node require hook, ts-node plugin, or JavaScript API. Listed integrations include Webpack, Gulp, Jest, Rollup, and Broccoli. Sucrase strips TypeScript and Flow annotations but does not check types, so its project recommends a separate typechecker or linter. It does not compile for older browsers such as Internet Explorer; unsupported syntax must be handled by the runtime or other tools. The project describes it as mainly useful in development, with Babel or tsc potentially more suitable for production. Sucrase is MIT-licensed, with TypeScript support and source maps; it has no plugin API.
Good
- Free and MIT-licensed
- Transforms JSX, TypeScript, and Flow
- Offers CLI and JavaScript API usage
- Lists integrations for Webpack, Jest, and Rollup
Watch out
- Does not check types
- Does not target older browsers such as Internet Explorer
- Transforms cannot be extended through a plugin API
Who it suits
Sucrase suits developers building for modern JavaScript runtimes who want transforms for development workflows. Projects needing type checking, older-browser compilation, or production builds may need separate or different tools.
Verdict
Sucrase covers common JavaScript development transforms and offers several ways to integrate it into a workflow. Account for its lack of type checking and older-browser compilation, and consider the project's guidance on production builds.
Plans and prices
From Sucrase's own pricing page, checked 9 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Sucrase | Free | MIT-licensed open-source project |
The facts
Each one read from Sucrase's own pages, with the date it was checked.
What it does
- Integrations
- The README lists Webpack, Gulp, Jest, Rollup, and Broccoli integrations, plus a ts-node plugin.checked 9 Oct 2026
- JavaScript syntax
- It transforms optional chaining, nullish coalescing, class fields, numeric separators, and optional catch binding by default.checked 9 Oct 2026
- Language transforms
- It transforms JSX, TypeScript, and Flow, and also supports import, React hot loader, and Jest transforms.checked 9 Oct 2026
- License
- Sucrase is MIT-licensed.checked 9 Oct 2026
- Plugins
- Sucrase is not pluginizable; its transforms must be explicitly implemented to cooperate with one another.checked 9 Oct 2026
- Production use
- The project says Sucrase is mostly beneficial in development and that Babel or tsc may be more suitable for production builds.checked 9 Oct 2026
- Purpose
- Sucrase is a fast alternative to Babel for development builds targeting modern JavaScript runtimes.checked 9 Oct 2026
- Runtime target
- Sucrase does not compile code for old browsers such as Internet Explorer, and unsupported syntax must be handled by the target runtime or other tooling.checked 9 Oct 2026
- Security and compliance
- The project page identifies an MIT license and does not state security certifications or compliance claims.checked 9 Oct 2026
- Type checking
- Sucrase removes TypeScript and Flow annotations but does not check types, so the project recommends using a separate typechecker or linter.checked 9 Oct 2026
- Usage
- Sucrase can be installed as an npm or Yarn development dependency and used through a CLI, Node require hook, ts-node plugin, or JavaScript API.checked 9 Oct 2026
