I'm really excited about https://sprites.dev/ - it hits two of my favourite problems at once:
1. Developer environment sandboxes. This is a cheap and convenient way to run Claude Code / Codex CLI / etc in YOLO mode in a persistent sandboxed VM with a restricted blast radius if something goes wrong.
2. Sandbox API. Fly now have a product that lets me make a simple JSON API call to run untrusted code in a new sandbox. There's even snapshotting support so I can roll back to a known state after running that code.
BTW Simon, I was super happy when I heard on Theo's podcast that he will be encouraging you to monetise your work more. I'm super appreciative of your work and I'm pretty convinced that the more you profit from it, the better the universe will be!!!
1. Developer environment sandboxes. This is a cheap and convenient way to run Claude Code / Codex CLI / etc in YOLO mode in a persistent sandboxed VM with a restricted blast radius if something goes wrong.
2. Sandbox API. Fly now have a product that lets me make a simple JSON API call to run untrusted code in a new sandbox. There's even snapshotting support so I can roll back to a known state after running that code.
I wrote more a bunch more about this here: https://simonwillison.net/2026/Jan/9/sprites-dev/