Show HN: Cryo – A language whose programs live forever

Cryo is a programming language that models long-running tasks like workflows or AI agents. Programs freeze to disk when idle and can be thawed when new data arrives.

As part of our announcement of Endothermic Labs, we've put together a small demo of Cryo that highlights its features and walks through the language and its plugin system.

We originally built it as a way to deploy healthcare agents at scale, but have rebuilt it from the ground up to be a standalone toolchain for long-running tasks. It acts as something like a cross between Durable Objects and Temporal workflows, where the script itself is the durable unit with no replay needed.

Cryo is statically and structurally typed, with a concurrency model similar to Go. It's still under active development, so we're holding off on open sourcing it until we're confident that the language is stable, ideally in the next 3-4 weeks.