The Deno team announced on October 9, 2026, that it is joining Cloudflare to merge the workerd and celld projects, aiming to simplify self-hosting for developers.
Merging Runtimes and Primitives
Ryan Dahl stated that the Deno team is joining Cloudflare to merge workerd and celld, allowing developers to use the same primitives in more places. Dahl noted that while Deno improved the JavaScript writing experience, networked applications presented larger problems around distributing computation, coordinating state, data storage, and autoscaling.
Cloudflare's Durable Objects provided a distributed singleton with a relational database, but running this model outside of Cloudflare remained difficult. To address this, Dahl started celld as an implementation of Workers and Durable Objects designed to be self-hostable and scalable.
Open Source and Leadership Plans
Kenton Varda of Cloudflare explained that the company open-sourced the Cloudflare Workers Runtime, workerd, after receiving feedback from customers like Shopify in 2022. Varda noted that while workerd is open source, its Durable Objects support was previously limited to a single instance and lacked a scalable self-hosting implementation.
Ryan Dahl and Bert Belder will lead a new effort at Cloudflare to make workerd self-hosting a first-class supported way to build and run apps using the Workers programming model. This will involve merging code and ideas from celld back into workerd.
Key facts and where they come from
- The Deno team is joining Cloudflare to merge workerd and celld.
The Deno team is joining Cloudflare, and we're merging workerd and celld!
- Ryan Dahl and Bert Belder will lead an effort to make workerd self-hosting supported.
Ryan and Bert will be leading a new effort to make workerd self-hosting a first-class supported way to build and run apps using the Workers programming model.
- Cloudflare open-sourced the Cloudflare Workers Runtime, workerd, following customer feedback.
the Cloudflare Workers Runtime, workerd, is open source.