Elysia
Elysia: A free, open-source TypeScript framework for building typed APIs on Bun. Ranked #23 of 31 in Web Frameworks by our editors (6.6/10); pricing: Free plan; best for typeScript teams building typed Bun-native APIs.
At a glance
- Editor score6.6 / 10
- PricingFree plan
- Best forTypeScript teams building typed Bun-native APIs
- Free planYes
- Paid fromFree
- Framework typeBackend
- Facts checked24 Sep 2026
Where it wins
- Infers route types and validates request and response schemas
- Combines routing with plugins and lifecycle hooks
- Generates OpenAPI docs and typed clients with Eden Treaty
Where it doesn't
- Backend-focused rather than broad full-stack coverage
- Designed around Bun runtime support
- Self-hosted deployment with docs and community support
Our verdict on Elysia
Elysia is an open-source backend web framework for developers building HTTP APIs and backend services with TypeScript or JavaScript. Its focus is Bun-native server development, with routing, schema validation, plugins and type inference brought together for teams that want API behavior and client types to stay connected. Solo developers through enterprise teams may use it, but its clearest fit is a TypeScript team building APIs on Bun rather than a project seeking a broad full-stack framework.
The standout is its typed API workflow. Elysia infers TypeScript types from routes and schemas, and supports request and response validation. Plugins and lifecycle hooks provide extension points around request handling. OpenAPI documentation generation makes the schema useful beyond the server itself, while Eden Treaty provides typed client tooling from Elysia servers. This combination can suit teams that want to define API behavior in the framework and share type information with client code. The tradeoff is focus: these features center on backend services and HTTP APIs, not broad full-stack coverage.
Elysia is free and open-source, with self-hosted deployment rather than a hosted SaaS plan structure. There are no paid tiers to weigh against the core framework in this model. Bun-native runtime support is central to its positioning, so teams choosing another runtime should assess that fit before adopting it. Support is through documentation and community channels. Pick Elysia if typed API development on Bun is the priority and a self-managed deployment works for your team. Choose a broader framework or another runtime-aligned option if you need full-stack coverage or are not building around Bun.
Your product? Our editors can test Elysia in depth and publish a review, labelled as paid · from $149/mo →
Elysia pricing
Elysia fact sheet
| Free plan | Yes |
|---|---|
| Paid from | Free |
| Framework type | Backend |
| Primary languages | TypeScript, JavaScript |
| Rendering modes | Not verified |
| Included ORM | Not verified |
| Built-in authentication | Not verified |
| Deployment targets | Self-hosted |
| License model | Open-source |
| Deployment | Self-hosted |
| Platforms | Web |
| Support | Docs, Community |
| Built for | Solo, Small business, Mid-market, Enterprise (editorial estimate) |
| Pricing | Free plan |
| Website | elysiajs.com |
| Facts checked | 24 Sep 2026 |
Alternatives to Elysia
- Ruby on RailsRails gives Ruby teams a convention-led, full-stack foundation for database-backed web apps.9.3
- DjangoA free Python backend framework combining ORM, authentication, administration, and deployment flexibility.9.1
- Next.jsA free, open-source full-stack React framework with hybrid rendering and backend routes.9.0
Used Elysia? Be the first to review it
The editor score above is our own research. What this page doesn't have yet is a reader's view — what you used Elysia for, what worked and what didn't. No stars are seeded and no review is paid for; an editor reads every one before it appears.
Write a reviewTwo minutes · verified accounts only · read by an editor before it appears
Featured on iTechGuides
Elysia is listed in our Web Frameworks directory. Add the badge to your site — it links back to this page.
<a href="https://www.itechguides.com/products/elysia/"><img src="https://www.itechguides.com/best/badge/elysia.svg" alt="Featured on iTechGuides" width="230" height="46"></a>
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.
Last updated · How we research and update