Show HN: Coasts – Containerized Hosts for Agents

Hi HN - We've been working on Coasts (“containerized hosts”) to make it so you can run multiple localhost instances, and multiple docker-compose runtimes, across git worktrees on the same computer. Here’s a demo: https://www.youtube.com/watch?v=yRiySdGQZZA . There are also videos in our docs that give a good conceptual overview: https://coasts.dev/docs/learn-coasts-videos . Agents can make code changes in different worktrees in isolation, but it's hard for them to test their changes without multiple localhost runtimes that are isolated and scoped to those worktrees as well. You can do it up to a point with port hacking tricks, but it becomes impractical when you have a complex docker-compose with many services and multiple volumes. We started playing with Codex and Conductor in the beginning of this year and had to come up with a bunch of hacky workarounds to give the agents access to isolated runtimes. After bastardizing our own docker-compose setup, we came up with Coasts as a way fo