hckrnws

The K8s-vs-agent-infra debate here is interesting. K8s gives you process and network isolation. What it doesn't give you: per-task authorization scope.

An agent container has a credential surface defined at deploy time. That surface doesn't change between task 1 ("read this repo") and task 2 ("process this user upload"). If the agent is prompt-injected during task 1, it carries the same permissions into task 2.

The missing primitives aren't infra — they're policy: what is this agent authorized to do with the data it can reach, on a per-task basis? Can it write, or only read? Can it exfil to an external URL, or only to /output? And crucially: is there an append-only record of what it actually did, so you can audit post-incident?

K8s handles the container boundary. The authorization layer above that — task-scoped grants, observable action ledger, revocation mid-task — isn't solved by existing infra abstractions. That gap is real regardless of whether you use K8s, Modal, or something like this.

K8s gives you orchestration of Docker containers. I don’t think it handles the container boundary any more than Docker does.

I don’t think it should be assumed to give network isolation, unless you’re also using extensions and something like Cilium for that purpose. I don’t think it’s the right primitive for agent sandboxes, or other kinds of agent infra.

(Obviously, you could still run a custom runtime inside k8s pods, or something like GCP’s k8s gVisor magic.)

This is really interesting, congrats on the launch. The use case I’m trying to solve for is building a coding agent platform that reliably sets up our development stack well. Few questions! In my case, I’m trying to build a one-shot coding agent platform that nicely spins up a docker-in-docker Supabase environment, runs a NextJS app, and durably listens to CI and iterates.

1) Can I use this with my ChatGPT pro or Claude max subscription? 2)

We don't support docker-in-docker yet, but that's something on our short term roadmap. We have the need for this ourselves! For now, you could call a different service to spin up your sandbox with the image of your codebase. Not ideal, but this is what we do now.

Yes, you can use your own subscriptions as long as you follow their guidelines

Hey I'm working on this problem (also a YC company but it's FOSS). It's a Dind approach https://coasts.dev/, I wonder if this works for your setup.

> We built Terminal Use to make it easier to deploy agents that work in a sandboxed environment and need filesystems to do work.

When I read this, I think of Fly.io's sprites.dev. Is that reasonable, or do you consider this product to be in a different space? If the latter, can you ELI5?

We overlap at the sandbox layer, but we're focused more on the layer above that: packaging agent code + deploying/versioning it, managing tasks over time, handling message persistence, and attaching durable workspaces to those tasks.

how does it compare to https://shellbox.dev? (and others like exe.dev, sprites.dev, and blaxel.ai)

We're trying to be a bit more opinionated one layer up: deployable agent runtimes with first-class tasks, persistent /workspace, and rollout/ops primitives like versions, rollback, logs, and secrets.

For example we make it easy to have automatic deployments from your github ci (using our cli), and you can monitor and manage all your deployments in our platform, along with logs, conversation transcripts etc.

I'd think of us more of the deployment, monitoring and storage layer rather than just the compute runtime.

have you guys found any of the existing nfs tools helpful (archil, daytona volumes, ...) or did you have to roll your own? i guess i have the same question for checkpointing/retrying too. it feels like the market of tools is very up in the air right now.

Yep, this whole area still feels pretty unsettled. The thing we've become convinced of is that workspace state needs to be a first-class product primitive instead of something tied to one sandbox. That's why we model filesystems separately from tasks and focus on durable mount/sync semantics.

We're currently rolling our own but we've been meaning to experiment with other tools.

howdy! two things on the archil front:

1. we're not NFS, we wrote our own protocol to get much better performance

2. we're planning on coming out with native branching this month, which should make these kinds of workloads much easier to build!

I'm using Dagger to checkpoint and all the fun stuff that can come after

is this a replacement to langgraph?

Can you explain why everyone thinks we should use new tools to deploy agents instead of our existing infra?

eg. I already run Kubernetes

Honest answer: the problems start when you're running 50+ agents across 3 different model providers and the failure modes aren't "pod crashed" anymore. They're "model returned confidently wrong output and the next 4 steps ran on garbage."

K8s is great at keeping things alive. It's not built to reason about whether the thing that's alive is actually working correctly. Agent infra needs to handle rollback at the logic level, not just the container level.

I think people pick new tooling not because k8s lacks horsepower, but because running per-user filesystem-backed agents on k8s forces you to build and maintain a surprising amount of glue code. Newer platforms put versioned mounts, local-first dev cycles, secure ephemeral runtimes, and opinionated deployment so teams can focus on agent logic instead of writing Helm charts and CSI gymnastics.

If you repurpose k8s with ephemeral volumes or emptyDir, a sidecar, you'll likely get predictable ops and avoid vendor lock-in. Expect more operator work, fragile debugging across PVCs and sidecars, and the need to invest in local emulation or a Firecracker or gVisor sandbox if you want anything like laptop parity.

Unrelated but your comments on https://news.ycombinator.com/item?id=44736176 related to the Terminal agents coding craze have helped me feel less crazy. People using GitHub Copilot CLI and Claude Code, they either never review the code or end up opening up an IDE to review the code, and I'm sitting here like, why don't you use the terminal in your favorite IDE? You're using a Terminal as a chat interface, so why not just use a chat interface? Or use the terminal in VS Code which actually now integrates very well with Claude Code and GitHub Copilot CLI so you can see what's going on across the many files this thing is editing?

The hype is so large with the CLI coding tools I got FOMO, but as you were saying in that thread, I see no tangible improvement to the value I get out of AI coding tools by using the CLI alone. I use the CLI in VS Code, and I use the chat panel, and the only thing that seems to actually make a difference is the "context engineering" stuff of custom instructions, agent skills, prompt files, hooks, custom agents, all that stuff, which works no matter which interface you use to kick off your AI coding instructions.

Would be curious to hear your thoughts on the topic all these months later.

Glad to find comradery! I've started the CLI interface to my custom agent since lol

The reasons are (1) it's faster to do admin work like naming or deleting old sessions (2) I have not gotten the remote setup to work yet (haven't tried) but I do want to use it somewhere

But yeah, it's gotten worse, the latest I recall is a new diff viewer for AI in the terminal (I already have git and lazygit)

I think there are some primitives for agents that need to be built out for better security and being able to reason about them.

Agents run on infra, they have network connectivity, they have ACLs and permissions that let them read+write+execute on resources, they can interact with other agents.

To manage them from both an infra and security perspective, we can use the existing underlying primitives, but it's also useful to build abstractions around them for management, kind of like how microservices encapsulate compute+storage+network together.

I think of agents as basically microservices that can act in non-deterministic ways, and the potential "blast radius" of their actions is very wide. So you need to be able to map what an agent can do, and it's much easier to do that if there are abstractions or automatic groupings instead of doing this all ourselves.

The "non-deterministic microservices" framing is exactly right and I think most infra teams underestimate how much that changes things. With a normal service, you can map inputs to expected outputs and write tests. With agents, the blast radius is probabilistic and context-dependent.

The monitoring problem alone is closer to fraud detection than traditional APM. You're not looking for "is this thing up," you're looking for "is this thing subtly wrong in a way that compounds over the next 10 steps."

The blast radius point is right, and I think it points at a design split that's underappreciated.

Most sandboxing approaches — including this one — optimize primarily for isolation from the host: prevent the agent from escaping, limit what it can touch. That solves the runaway agent problem.

But there's a second axis: observable execution for human collaborators. When an agent modifies a codebase or runs a research task, a teammate often needs to watch it happen in real time, intervene before it commits a wrong turn, or audit what actually ran. Async logs and artifact outputs don't cover this well.

We've been building Cyqle - https://cyqle.in -- (disclosure: I work on it) from that angle — cloud desktop sessions where agent runs are shared live with whoever needs visibility. Isolation is at the VM/session level rather than syscall granularity. Different tradeoff: you give up process-level permission mapping, you gain real-time collaborative access to the running environment — watch, intervene, hand off.

The use cases probably don't overlap much with Terminal Use (async batch filesystem agents clearly want deep process isolation + lifecycle APIs). But this thread made me think "agent environments" is actually several distinct problem spaces: async autonomous execution, interactive human-supervised sessions, team-observable debugging runs. The right primitives look very different depending on which you're solving.

Right, those abstractions and controls already exist in the Kubernetes ecosystem. I can use one set of abstractions for everything, as opposed to having something separate for agents. They are not that different, the tooling I have covers it. There are also CRDs and operators to extend for a more DSL like experience.

tl;dr, I don't think the shovel analogy holds up for most of the Ai submissions and products we see here.

I think Kubernetes is a good candidate to run these sandboxes. It is just that you have to do a lot of annotations, node group management, pod security policies, etc., to name a few. Apply the principle of least privilege for access to mitigate risk.

I think Kata containers with Kubernetes is an even better sandboxing option for these agents to run remotely.

Shameless plugin here but we at Adaptive [1] do something similar.

[1] https://adaptive.live

We already do those things with k8s, so it's not an issue

The permissions issues you mention are handled by SA/WIF and the ADK framework.

Same question to OP, why do you think I need a special tool for this?

We have also built something custom ourselves (with modal.com serverless containers), running thousands of on-demand coding agents each day and already the assumptions that Terminal Use is making (about using the file system and coding agent support) would not work for our use case.

It seems like so many of the AI "solutions" are hallucinating the problems. I either don't have them, because I use better AI frameworks, or I have tools at hand that solve them nicely.

We don't need to rebuild everything just for agents, except that people think they can make money by doing so. YC has disappointed me of late with the lack of diversity in their companies. I suspect the change in leadership is central to this.

At least on K8s you can control the network policy. That's the harder problem to solve. I suspect we'll see a lot of exfiltration via prompt injection in the next few years.

[dead]

[dead]