Hacker News: Finbarr

New comment by Finbarr in "RubyLLM: A Ruby framework for all major AI providers"

Finbarr — Wed, 24 Jun 2026 15:46:23 +0000

RubyLLM is very easy to use. Made extensive use of it for a project last year. Drawbacks are it was difficult to instrument for true trace observability and it has a pattern where retries will delete the underlying models so the history you see is clean but not necessarily great for seeing exactly what the sequence of API calls was.

Sakana Fugu

Finbarr — Mon, 22 Jun 2026 02:08:18 +0000

Article URL: https://sakana.ai/fugu/

Comments URL: https://news.ycombinator.com/item?id=48624782

Points: 247

# Comments: 126

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Wed, 06 May 2026 15:31:14 +0000

Interesting suggestion, thank you!

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Wed, 06 May 2026 15:30:35 +0000

I wouldn't assume that a VM will give you complete security against a determined AI. yolobox started as a way to prevent accidental `rm -rf ~` and has expanded into a set of tools that make working with CLI agents easier.

Personally, I run yolobox directly on the host. Being able to tell the agent it has sudo and can install and do whatever it needs to accomplish any task is handy.

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Wed, 06 May 2026 15:28:33 +0000

Docker was only exposed later, after I realized that any sufficiently determined AI could break out of the container, and attempts to contain it were a waste of time. Also note that the docker socket is not exposed by default. There's a --docker flag for this.

I made some comments about exploits in the original post [1]. Gemini was quite creative in adding git hooks to the repo that would execute on the host machine. That folder is shared.

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Wed, 06 May 2026 14:15:18 +0000

The docker compose stack for the applications is spun up on the host. The agents have access to the docker socket which means they can talk to docker from inside their sandbox and spin up new sibling containers on the host. Yolobox isn’t designed for full isolation- just accidental commands you wouldn’t want to run on the host, and a convenient way of giving agents a customizable environment they control.

Early on in development I tried to harden the container to prevent deliberate escapes by the agent. This was a waste of time as the agents just kept finding more and more exploits when I asked them to try and break out.

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Tue, 05 May 2026 20:57:11 +0000

Did you read the post? That's exactly the problem I just solved.

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Tue, 05 May 2026 20:36:34 +0000

VMs bring greater isolation but they're a lot heavier and slower. The agents just use github for synchronization here, though I've been considering building some kind of todo list overlay locally.

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Tue, 05 May 2026 17:07:30 +0000

Hard drives are cheap and I haven't approached the limit yet. So I left this as a future optimization.

New comment by Finbarr in "Treat your coding agents like developers"

Finbarr — Tue, 05 May 2026 16:47:46 +0000

Author here. Three months ago I posted a Show HN for yolobox [1] - a sandbox for running AI coding agents without them being able to nuke your home directory.

Since then I've been using it almost every day, which eventually meant wanting more than one agent running against the same project at the same time. This post is what I learned trying to make that work without it being a constant disaster.

The short version: git worktrees are the right Git abstraction and the wrong abstraction for this problem. The unit you want to fork is the developer, not the branch - full folder copy, its own Compose project, its own URL. yolobox now ships a fork subcommand that does this.

Happy to answer questions.

[1] https://news.ycombinator.com/item?id=46592344

Treat your coding agents like developers

Finbarr — Tue, 05 May 2026 16:46:00 +0000

Article URL: https://finbarr.site/2026/05/05/treat-your-coding-agents-like-developers.html

Comments URL: https://news.ycombinator.com/item?id=48025013

Points: 24

# Comments: 16

How I sequenced my genome at home

Finbarr — Sun, 19 Apr 2026 16:16:24 +0000

Article URL: https://twitter.com/sethshowes/status/2045782975380406623

Comments URL: https://news.ycombinator.com/item?id=47825381

Points: 18

# Comments: 5

New comment by Finbarr in "Stop Flock"

Finbarr — Thu, 16 Apr 2026 01:08:44 +0000

I think you're making some hasty generalizations here. They don't "uniformly" cover for their colleagues. Do you expect the police service to be perfect and never make mistakes? Can you point me towards a single human-run service where that's the case?

New comment by Finbarr in "Stop Flock"

Finbarr — Wed, 15 Apr 2026 15:48:26 +0000

County was not a typo. It's awful whenever there's an overuse of force in the USA. I'd recommend watching a few police bodycam videos on youtube before judging them wholesale though. The experience of a police officer in the United States seems to be long periods of tedium punctuated by moments of sheer terror and adrenaline. Anyone out there can have a gun and encounters can unexpectedly escalate to deadly violence in seconds. Some of them should not be police officers. There are many great officers out there just trying to protect their communities.

New comment by Finbarr in "Stop Flock"

Finbarr — Wed, 15 Apr 2026 05:26:51 +0000

Agreed. Flock has been a key contributor in solving numerous crimes. I'm happy for Flock to be in my county and would like the police to have more access to technology like this, not less.

New comment by Finbarr in "The Claude Code Leak"

Finbarr — Thu, 02 Apr 2026 05:51:39 +0000

Who cares that the code is garbage? As the models get bigger and more powerful it will be trivial to fully refactor the whole codebase. It’s coming sooner than you think.

New comment by Finbarr in "Multiple Sclerosis"

Finbarr — Tue, 31 Mar 2026 18:52:23 +0000

MS treatments tend to take 3 forms:

- immune reset (sledgehammer that can “cure” diseases like MS but with many side effects and potential complications)

- immune suppression (super effective but with increased risk of infections and blunts vaccines)

- immune redirection (less effective but doesn’t mess up your immune system so badly).

It’s only in the last ~10 years that super effective treatments that can stop ~99% of lesion progression have existed- Ocrevus and Kesimpta. These are anti CD20 disease modifying therapies that destroy all your B cells. The memoir of Dr. Stephen Hauser- “The Face Laughs While The Brain Cries”- provides a fascinating insight into the development of these treatments over the last ~40 years of his career.

There are active trials of newer types of treatment and a lot of progress is being made in the MS space. It used to be a “death sentence” disease but is quite manageable for many sufferers now. It’s different for every individual and I wish the blog author good health.

New comment by Finbarr in "Agent Safehouse – macOS-native sandboxing for local agents"

Finbarr — Mon, 09 Mar 2026 01:08:37 +0000

Awesome to see a bash-only method of solving this problem. Also like that it alerts on attempts to read restricted stuff.

I built yolobox to solve this using docker/apple containers: https://github.com/finbarr/yolobox

Trump Responds to Anthropic

Finbarr — Fri, 27 Feb 2026 21:16:46 +0000

Article URL: https://twitter.com/PeteHegseth/status/2027487514395832410

Comments URL: https://news.ycombinator.com/item?id=47185735

Points: 8

# Comments: 0

New comment by Finbarr in "AI is going to kill app subscriptions"

Finbarr — Sun, 15 Feb 2026 15:36:56 +0000

I wrote an article about this a few days ago that has been gaining a lot of traction: https://finbarr.site/2026/02/12/in-defense-of-saas.html

Point solutions are going to be free. Complex systems with support, integrations, switching costs, customer data, etc., are not going to be free.