Fence – Sandbox CLI commands with network/filesystem restrictions
Hi HN! Fence wraps any command in a sandbox that blocks network by default and restricts filesystem writes. Useful for running semi-trusted code (package installs, build scripts, unfamiliar repos) with controlled side effects, or even just blocking tools that phone home. > fence curl https://example.com # -> blocked > fence -t code -- npm install # -> template with registries allowed > fence -m -- npm install # -> monitor mode: see what gets blocked One use-case is to use it with AI coding agents to reduce the risk of running agents with fewer interactive permission prompts: >…
Fence – Sandbox CLI commands with network/filesystem restrictions launched on January 20, 2026 with 78 votes, #441 of 14,585 launches that month and more than 95% of that year's launches.
In plain words
Fence is a command-line sandbox tool that restricts network access and filesystem writes when executing commands. It blocks all network traffic by default and prevents unintended file modifications, making it useful for running untrusted code like package installations, build scripts, or unfamiliar repositories safely. It offers templates for common tasks like npm installs, a monitor mode to observe blocked actions, and integration with AI coding agents to reduce permission prompts.
written from the facts on this page · September 2026
From the sources
Lightweight, container-free sandbox for running commands with network and filesystem restrictions - fencesandbox/fence
In the maker’s words, at launch
Hi HN! Fence wraps any command in a sandbox that blocks network by default and restricts filesystem writes. Useful for running semi-trusted code (package installs, build scripts, unfamiliar repos) with controlled side effects, or even just blocking tools that phone home. > fence curl https://example.com #…
Does a similar job
all alternatives →
Zerobox – Sandbox any command with file, network, credential controlsMar 2026 · github.com · ▲141I'm excited to introduce Zerobox, a cross-platform, single binary process sandboxing CLI written in Rust. It uses the sandboxing crates from the OpenAI Codex repo and adds additional functionalities like secret injection, SDK, etc. Watch the demo: https://www.youtube.com/watch?v=wZiPm9BOPCg Zerobox follows the same sandboxing policy as Deno which is deny by default. The only operation that the command can run is reading files, all writes and network I/O are blocked by default. No VMs, no Docker, no remote servers. Want to block reads to /etc? zerobox…
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More ai this month
the category →
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Source: Show HN post ↗ · launch text quoted in part
Launched alongside, January 2026
the whole month →- IN
Hey HN! I wanted to share something I built over the last few weeks: isometric.nyc is a massive isometric pixel art map of NYC, built with nano banana and coding agents. I didn't write a single line of code. Of course no-code doesn't mean no-engineering. This project took a lot more manual labor than I'd hoped! I wrote a deep dive on the workflow and some thoughts about the future of AI coding and creativity: http://cannoneyed.com/projects/isometric-nyc
AI · Jan 2026 · cannoneyed.com
Automatic AI-powered code reviews the moment you open a PR
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