# Bert Belder (slim)

> Bert Belder is deno co-founder and CTO; now Cloudflare workerd self-hosting lead. Deno Sandbox on Anchor Terminal, with grades, an about and public profiles.

- Full: https://www.anchorterminal.com/people/bert-belder/index.md (~1,150 tokens) · this version ~830 tokens · JSON https://www.anchorterminal.com/people/bert-belder/index.json · canonical https://www.anchorterminal.com/people/bert-belder/
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-10-28
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

Deno co-founder and CTO; now Cloudflare workerd self-hosting lead.

Bert Belder co-created the Deno JavaScript and TypeScript runtime with Ryan Dahl at Deno Land.

- LinkedIn: https://www.linkedin.com/in/bertbelder

## What Bert builds

- [Deno Sandbox](https://www.anchorterminal.com/tools/deno-sandbox.md), graded D, 50.4/100, in Code execution sandboxes. Deno Sandbox runs Linux microVMs on Deno Deploy for untrusted or AI-generated code. It is driven from the `@deno/sandbox` JavaScript SDK, the `deno-sandbox` Python SDK or the `deno sandbox` CLI, and launched in beta on 3 February 2026. Deno co-founder and CTO; now Cloudflare workerd self-hosting lead, researched 2026-10-27.

## Works with

- [Ryan Dahl](https://www.anchorterminal.com/people/ryan-dahl/), Deno co-founder; Sandbox launch author; now Cloudflare workerd self-hosting lead

## Backed by

- [Four Rivers](https://www.anchorterminal.com/investors/four-rivers/)
- [Rauch Capital](https://www.anchorterminal.com/investors/rauch-capital/)
- [Long Journey Ventures](https://www.anchorterminal.com/investors/long-journey-ventures/)
- [Mozilla](https://www.anchorterminal.com/investors/mozilla/)
- [Shasta Ventures](https://www.anchorterminal.com/investors/shasta-ventures/)
- [Ben Noordhuis](https://www.anchorterminal.com/investors/ben-noordhuis/)
- [Sequoia Capital](https://www.anchorterminal.com/investors/sequoia-capital/)
- [Insight Partners](https://www.anchorterminal.com/investors/insight-partners/)
- [Automattic](https://www.anchorterminal.com/investors/automattic/)
- [Netlify](https://www.anchorterminal.com/investors/netlify/)
- [Nat Friedman](https://www.anchorterminal.com/investors/nat-friedman/)
- [Dylan Field](https://www.anchorterminal.com/investors/dylan-field/)

## Questions

### Who is Bert Belder?

Bert Belder co-created the Deno JavaScript and TypeScript runtime with Ryan Dahl at Deno Land.

### What does Deno Land Inc. make?

Anchor Terminal lists Deno Sandbox from Deno Land Inc..

### Who has invested in Deno Land Inc.?

The sources our research read name Four Rivers, Rauch Capital, Long Journey Ventures, Mozilla, Shasta Ventures, Ben Noordhuis, Sequoia Capital, Insight Partners, Automattic, Netlify, Nat Friedman and Dylan Field.

### How are Bert's tools graded?

Deno Sandbox is graded D, 50.4 out of 100, on Anchor Terminal's benchmark, which scores every listing against the same checklist.

## Sources

- https://deno.com/blog/introducing-deno-sandbox
- https://deno.com/blog/cloudflare
- https://blog.cloudflare.com/deno-joins-cloudflare/
- https://x.com/rough__sea
- https://www.linkedin.com/in/bertbelder
- https://deno.com/
- https://deno.com
- https://www.linkedin.com/company/deno
- https://docs.deno.com/sandbox/

These are the people building the tools we list, named for their public role in the company or project behind a listing, from public pages, with the date it was researched.