Cloudflare Workers on Your Own Servers, With Deno's Help

What Was Announced

On October 9, 2026, Cloudflare and Deno announced that the whole Deno team is joining Cloudflare. Ryan Dahl, who created Node.js and later Deno, will lead the work together with Bert Belder. Their job is to make workerd, the open source runtime behind Cloudflare Workers, "a first-class supported way" to build and run apps on the Workers model, on your own machines as well as on Cloudflare's. Neither company disclosed financial terms.

The Missing Piece Was Durable Objects

workerd has been open source for years, and Cloudflare says it is the same code that runs Workers in production. You could already run a Worker with it on your own server. What you could not do was run Durable Objects at scale, because workerd runs them as a single instance, which is enough for local testing and not for production. That matters more than it sounds, since Cloudflare builds services such as Queues and its Workflows API on top of Durable Objects.

In August the Deno team released celld, an open source implementation of Workers and Durable Objects written for self-hosting. It ships as one Rust binary, and its only external dependency is object storage. Code and ideas from celld will now be merged into workerd.

What It Means if You Build on Workers

The usual objection to Workers is lock-in, because code written for Workers has had one realistic place to run. Cloudflare's Kenton Varda answers that point directly in the announcement, and says some large customers would not have signed up at all without an open source runtime behind the platform.

A supported self-hosted workerd would give a Workers app a second home, on your own servers, in another cloud or in a private network, without a rewrite. Cloudflare says more announcements will follow "in the coming months". Until then celld and workerd can be self-hosted as they are, but the merged and supported version does not exist yet, so treat it as a direction rather than something to migrate to today.

What Changes for Deno Users

Deno's own post, written by Ryan Dahl, sets out the timeline.

• Deno Deploy keeps running for six months and then shuts down. Paying customers get help moving to Cloudflare Workers.
• The Deno runtime gets one more year of monthly releases with bug fixes and security updates. After that the team stops developing it. Deno stays open source, so others can carry it on.
• JSR, the JavaScript package registry, keeps running, and its infrastructure moves to Cloudflare.

What to Do Now

1. Apps on Deno Deploy. Start planning the move this month. Six months is enough for an inventory, a test deploy on the new platform and a quiet cutover, with little slack beyond that. Workers is the path Deno points to, and a small container on any host is the other common choice.
2. The Deno runtime on your own servers. You have a year of security updates. Use it to decide between Node.js, Bun or a community fork, and make the switch while patches still arrive, not after.
3. Workers, held back by lock-in. Nothing to change yet. Watch the workerd self-hosting work, since it may remove the main reason to hesitate.

Where It Fits

Cloudflare has been opening up more of its platform this year, from free threat intelligence for every account to its new free certificate authority. Deciding where code runs, and how hard it would be to move it later, is part of our architecture planning work, and so is a platform move like leaving Deno Deploy.

Sources

• Cloudflare blog: Deno is joining Cloudflare
• Deno blog: Deno is joining Cloudflare
• TechCrunch: Cloudflare acquires Deno to improve its Workers programming model