Self-host a sandbox for code your agent writes
Built Plimsoll, a self-hosted sandbox service for untrusted agent-authored code with isolation reporting.
Source
cagster on Hacker News · 2026-10-11 · Project link
Written in our own words. Credit to the original author. Link checked 2026-10-15.
What they did
Built Plimsoll, a self-hosted sandbox service for untrusted agent-authored code with isolation reporting.
Result (as claimed)
Open-sourced sandbox focused on agent-written code safety.
Tools they used
The source does not name specific tools.
Cost: Pricing depends on the tools you pick; check each official pricing page.
Set it up
Pick a contained repo or task
Start on a branch or side project where mistakes are cheap.
Install and configure
Set up the tools you choose. Read what it can run on your machine and limit permissions where possible.
Run it on a real task
Give it a well-scoped issue and let it work. Review the diff like any pull request.
Add guardrails
Keep tests and CI in the loop, and never let an agent push to main or touch production secrets unattended.
Copy the full setup prompt
Paste into your agent and it will walk you through the setup, asking before anything that sends, posts or spends.
You are helping me set up this AI use case end to end in Claude Code. Goal: Self-host a sandbox for code your agent writes What the original author did: Built Plimsoll, a self-hosted sandbox service for untrusted agent-authored code with isolation reporting. Reported result (as claimed by the author): Open-sourced sandbox focused on agent-written code safety. Source: https://news.ycombinator.com/item?id=50049388 Tools they used: not named in the source Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Codex. Goal: Self-host a sandbox for code your agent writes What the original author did: Built Plimsoll, a self-hosted sandbox service for untrusted agent-authored code with isolation reporting. Reported result (as claimed by the author): Open-sourced sandbox focused on agent-written code safety. Source: https://news.ycombinator.com/item?id=50049388 Tools they used: not named in the source Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Grok Bot. Goal: Self-host a sandbox for code your agent writes What the original author did: Built Plimsoll, a self-hosted sandbox service for untrusted agent-authored code with isolation reporting. Reported result (as claimed by the author): Open-sourced sandbox focused on agent-written code safety. Source: https://news.ycombinator.com/item?id=50049388 Tools they used: not named in the source Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
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