Cloudflare to acquire Deno for Workers

Cloudflare announced Friday that it is acquiring Deno, the startup behind the Deno JavaScript and TypeScript runtime, in a transaction aimed at improving its Workers programming model and platform. The companies did not disclose financial terms.

Deno said its entire team is joining Cloudflare. The company also said the Deno runtime will receive monthly bug-fix and security releases for one more year before official development ends, though it will remain open source. Deno Deploy, the company’s application hosting service, will continue for six months before shutting down, and paying customers will get migration support as they move to Cloudflare Workers. JSR, Deno’s package registry, will continue operating, with its infrastructure moving to Cloudflare.

Why is Cloudflare acquiring Deno?

Cloudflare said the acquisition is meant to improve its Workers programming model, which lets customers build and run software on Cloudflare’s network. TechCrunch reported that Kenton Varda, Cloudflare’s principal engineer for Workers, wrote that celld had "delighted" the Cloudflare team. Deno said celld is an open-source implementation of Workers built on the Workers programming model.

Deno’s own explanation for the deal centers on reducing infrastructure complexity for developers. The company said its original ambition went beyond a standalone runtime to "compute, storage, and communication working together," and said building Deno Deploy showed how much complexity remains under that developer experience. Deno said celld lets developers build distributed applications from the start while keeping the system simple to operate, with Ryan Dahl saying the scaling is built into the programming model rather than app-specific infrastructure.

What happens to Deno’s products and team?

The immediate effect is a phased transition. Deno said the runtime will keep getting monthly maintenance and security updates for one year, then official development will stop. The runtime supports JavaScript and TypeScript applications.

For Deno Deploy customers, the timeline is shorter. Deno said the service will continue for six months before shutting down, and Cloudflare will support paying customers through the move to Workers. JSR will remain available, but its backend infrastructure will move under Cloudflare’s control. Deno also said Cloudflare will keep supporting rusty_v8 and work toward integrating it into workerd, Cloudflare’s server-side runtime component for Workers.

What does this mean for Deno’s founders and backers?

Deno was co-founded by Ryan Dahl, who also created Node.js, along with Bert Belder. TechCrunch reported that Deno had raised $26 million in total, including a Series A led by Sequoia, as background financing history.

Deno framed the move as part of a broader push toward simpler distributed systems. The company said the need for better abstractions is especially acute with AI, and described Durable Objects as useful for agent harnesses because they combine serverless execution, persistent state, WebSockets, and a JavaScript interface. Deno also said Ryan Dahl and Kenton Varda had published a joint post on the Cloudflare blog explaining more about the move.