This is pretty cool, have personally felt this limitation many a time.
Basically been relying on spinning up cursor / niteshift / devin workflows since they have their own containers but this could be interesting to keep it all on your main machine.
You could... sort of. We started out with this in mind. We wanted to get Claude Max plans to work so we built a way to inject OAuth secrets from the host into the containerized host... unfortunately because the Coast runtime doesn't match the host machine the OAuth token is created on, Anthropic rapidly invalidates the OAuth tokens. This would really only work for TUIs/CLIs and you'd almost certainly have to bring a usage key (at least for Anthropic). You would also need to figure out how to get a browser runtime into the containerized host if you wanted things like playwright to work for your agent.
There's so many good host-side solutions for sandboxing. Coasts is not a sandboxing tool and we don't try to be. We should play well with all host-side sandboxing solutions though.
2) Why DinD and why not mount namespaces with unshare / nsenter?
Yes, DinD is heavy. A core principle of our design was to run the user's docker-compose unmodified. We wanted the full docker api inside the running containerized host. Raw mount namespaces can't provide image caches, network namespaces, and build layers without running against the host daemon or reimplementing Docker itself.
In practice, I've seen about 200mb of overhead with each containerized host running Dind. We have a Podman runtime in the works, which may cut that down some. But the bulk of utilization comes from the services you're running and how you decide to optimize your containerized hosts and docker stack. We have a concept of "shared-services". For example if you don't need isolated postgres or redis, you can declare those services as shared in your Coastfile, and they'll run once on the host Docker daemon instead of being duplicated inside each containerized host, coasts will route to them.
This is pretty cool, have personally felt this limitation many a time.
Basically been relying on spinning up cursor / niteshift / devin workflows since they have their own containers but this could be interesting to keep it all on your main machine.
Thanks!
Yeah, I think there's a ton of great remote solutions right now. I think worktrees make the local stuff tricky but hopefully Coasts can help you out.
Let me know how it goes!
HN questions we know are coming our way:
1) Could you run an agent in the coast?
You could... sort of. We started out with this in mind. We wanted to get Claude Max plans to work so we built a way to inject OAuth secrets from the host into the containerized host... unfortunately because the Coast runtime doesn't match the host machine the OAuth token is created on, Anthropic rapidly invalidates the OAuth tokens. This would really only work for TUIs/CLIs and you'd almost certainly have to bring a usage key (at least for Anthropic). You would also need to figure out how to get a browser runtime into the containerized host if you wanted things like playwright to work for your agent.
There's so many good host-side solutions for sandboxing. Coasts is not a sandboxing tool and we don't try to be. We should play well with all host-side sandboxing solutions though.
2) Why DinD and why not mount namespaces with unshare / nsenter?
Yes, DinD is heavy. A core principle of our design was to run the user's docker-compose unmodified. We wanted the full docker api inside the running containerized host. Raw mount namespaces can't provide image caches, network namespaces, and build layers without running against the host daemon or reimplementing Docker itself.
In practice, I've seen about 200mb of overhead with each containerized host running Dind. We have a Podman runtime in the works, which may cut that down some. But the bulk of utilization comes from the services you're running and how you decide to optimize your containerized hosts and docker stack. We have a concept of "shared-services". For example if you don't need isolated postgres or redis, you can declare those services as shared in your Coastfile, and they'll run once on the host Docker daemon instead of being duplicated inside each containerized host, coasts will route to them.
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