Cloudflare is buying the startup co-founded by Node.js creator Ryan Dahl, a longtime competitor that recently built its own open-source version of Cloudflare’s serverless computing platform.
The company announced on Friday that the entire team behind Deno, the JavaScript and TypeScript runtime, is joining Cloudflare. Deno’s standalone runtime and cloud hosting service will be wound down, with its engineers turning their attention to Cloudflare Workers, the serverless computing platform unveiled in 2017 that allows developers to run applications without managing the underlying infrastructure.
Terms of the deal were not disclosed.
Deno’s Cloudflare-inspired project
Deno emerged in 2018 as Dahl’s attempt to address shortcomings in Node.js, particularly around security and dependency management. The startup, which raised around $26 million in funding across two rounds, later launched Deno Deploy, putting it in direct competition with Cloudflare Workers.
The companies have also experienced more than a little friction through the years. In 2021, Cloudflare mistakenly blocked Deno’s website and module registry after incorrectly identifying TypeScript files as video content, forcing Deno to move infrastructure elsewhere.
“Celld is a love letter to their idea; a primitive this good deserves to run anywhere.”
Then back in August, Deno introduced Celld, an open-source project that recreated Cloudflare’s Workers and Durable Objects programming model, for developers wanting to run distributed applications on their own infrastructure.
Deno made no secret of the inspiration. On the Celld website, the company explicitly credited Cloudflare distinguished engineer Kenton Varda and the Workers team for the underlying design, describing its project as a tribute to their work.
“Celld is a love letter to their idea; a primitive this good deserves to run anywhere,” the website states.
The admiration, it seems, was mutual. In a joint blog post published on Friday, Varda praised Deno’s expertise in an area where Cloudflare had perhaps struggled.
“The Deno team understands how to create a good developer experience around a self-hosted runtime — something we never quite cracked with workerd,” Varda writes.
Moreover, he also acknowledges that Cloudflare has struggled to make its open-source Workers runtime practical for developers operating outside its network.
“Frankly, we haven’t done a great job of building out the ecosystem of adjacent services and tooling to make it really work.”
“Frankly, we haven’t done a great job of building out the ecosystem of adjacent services and tooling to make it really work,” Varda continues. “We’d released the runtime, and then we sort of just hoped the community would step in and start adapting it to every possible environment.”
What’s next for Workers and Deno
Cloudflare now plans to merge Celld with Workerd, its existing open-source runtime, with Dahl and Deno co-founder Bert Belder leading the effort. The aim, ultimately, is to make it easier to build and operate distributed applications using Cloudflare’s programming model on independently managed infrastructure.
In an email Q&A, Dahl says the combined project is expected to remain open source, likely under the Apache 2.0 license already used by Celld. He also outlines how developers would be able to operate it without relying on Cloudflare’s infrastructure.
“Running a fleet of workerd instances will require only an industry-standard object storage bucket for coordination and storage,” Dahl tells The New Stack. “The API will be the same as Cloudflare’s own platform — which is a good thing.”
Asked what guarantees developers would have against vendor lock-in, Dahl argues that the project’s licensing and the team’s intentions were central to its independence.
“We believe only the open version wins here, because anything this fundamental to the future of how developers build on the web needs to be inspectable, portable, and usable outside a single vendor’s platform,” he continues. “We wouldn’t be trying this any other way but open, as there’d be no point.”
“We believe only the open version wins here, because anything this fundamental to the future of how developers build on the web needs to be inspectable, portable, and usable outside a single vendor’s platform.”
This decision also means Deno will stop developing its standalone runtime and hosting service, with the team instead focusing its efforts on the combined platform. The Deno runtime will receive monthly maintenance and security updates for another year, while Deno Deploy will shut down in six months, with migration assistance for paying customers. The JSR package registry will continue under Cloudflare.
Asked how much competition with Cloudflare Workers had influenced the move, Dahl points to the similarities between the two platforms and Deno’s increasing compatibility with Node.js.
“Deno Deploy was built towards the same ideals as Workers, this is why joining forces made so much sense,” he explains.
As for the runtime itself, Dahl says its growing compatibility with Node.js had effectively left Deno maintaining another implementation of the same technology.
“Many love the Deno runtime, and it remains MIT-licensed, but there are bigger problems that can be solved with a distributed programming model,” he adds.
JavaScript runtimes find a new home in AI
For what it’s worth, the acquisition follows Anthropic’s purchase of Bun in December 2025, which brought another prominent Node.js alternative under the ownership of a larger technology company. There is a key difference, however: Anthropic committed to continuing Bun’s development as an open-source JavaScript runtime, whereas Deno’s runtime development will end with its transition to Cloudflare.
In a separate blog post published on Friday, Dahl also highlights AI agents as an important application for the technology, particularly as developers look for simpler ways to manage the infrastructure underpinning them.
“The need for better abstractions is especially acute with AI,” Dahl writes. “Durable Objects bring together capabilities that are particularly useful for agent harnesses: inexpensive, serverless execution, persistent state, WebSockets, and a high-level JavaScript interface.”
For Cloudflare, the acquisition brings in an experienced engineering team and technology that addresses a longstanding gap in its Workers platform. For Deno, it marks the end of its independent runtime ambitions, even as the Cloudflare-inspired project it launched just two months ago becomes central to its future.