{"slug": "just-bash", "name": "just-bash", "category": "terminal", "category_name": "Terminal and shell", "description": "", "recommenders": 4, "commenters": 15, "warners": 2, "score": 3.312, "rising": -1.31, "first": "2026-01-30", "latest": "2026-10-17", "why": "I love the approach of just bash as well. Super cool!", "why_is_quote": true, "has_verdict": false, "sentiment": {"recommend": 4, "neutral": 8, "compare": 2, "warn": 2}, "spark": [0, 0, 1, 2, 1, 0, 0, 0, 0, 0, 0, 0], "listed": true, "loved": [], "caveat": "", "short_quote": "I love the approach of just bash as well. Super cool!", "kind": "", "icon": true, "domain": null, "github_repo": "github.com/vercel-labs/just-bash", "official_url": "https://github.com/vercel-labs/just-bash", "pricing": "", "aliases": ["just-bash"], "verdict": null, "praise": [{"label": "", "summary": "", "quotes": [{"id": 755363601, "item_id": 47210225, "url": "https://news.ycombinator.com/item?id=47210225", "by": "goodmodule", "date": "2026-03-01", "version": null, "stance": "recommend", "quote": "For CLI and file operations we have Vercel's just-bash", "excerpt": "I somehow agree with this but want to add my two cents here. Cloudflare's Codemode[0] is a great \"replacement\" for MCP because AI is trained for writing code and handling errors. But it also doesn't fix security and sandboxing. For CLI and file operations we have Vercel's just-bash[1] but for everything else there is no safe solution. Therefore MCP still makes sense until somebody sandboxes this part as well without ", "context": "", "use_case": "Sandboxed CLI and file ops", "switched_from": "", "story": "MCP is dead. Long live the CLI"}, {"id": 754858865, "item_id": 47178679, "url": "https://news.ycombinator.com/item?id=47178679", "by": "thoughtfulchris", "date": "2026-02-27", "version": null, "stance": "recommend", "quote": "I love the approach of just bash as well. Super cool!", "excerpt": "I'm hacking on a similar thing that lets you build CLIs directly into xterm / ghostty web so that they also work in the terminal. Eg they are cross platform web and CLI. Demo: https://wizard-nine-blush.vercel.app/ Project: https://ink-web.dev I love the approach of just bash as well. Super cool! Edit: warning - don't use it mobile.", "context": "", "use_case": "bash for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754756368, "item_id": 47172273, "url": "https://news.ycombinator.com/item?id=47172273", "by": "rbbydotdev", "date": "2026-02-26", "version": null, "stance": "recommend", "quote": "It\u2019s cool to see this project and others pop up.", "excerpt": "It\u2019s cool to see this project and others pop up. Virtualizing os primitives like bash and even file systems You can interface around the nodejs files system interface and have access to some nice tools, like git isomorphic for instance. Then obviously everything couples nicely with agents. Something I did in my markdown editor project: https://github.com/rbbydotdev/opal Have half a mind to release a browser kit which", "context": "", "use_case": "virtual bash for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 749264768, "item_id": 46829048, "url": "https://news.ycombinator.com/item?id=46829048", "by": "simonw", "date": "2026-01-30", "version": null, "stance": "recommend", "quote": "Sounds like just-bash:", "excerpt": "Sounds like just-bash: https://github.com/vercel-labs/just-bash", "context": "", "use_case": "", "switched_from": "", "story": "Show HN: Amla Sandbox \u2013 WASM bash shell sandbox for AI agents"}]}], "caveats": [{"label": "", "summary": "", "quotes": [{"id": 757161474, "item_id": 47322592, "url": "https://news.ycombinator.com/item?id=47322592", "by": "simonw", "date": "2026-03-10", "version": null, "stance": "warn", "quote": "I'd rather run a 10MB WASM bundle with a full existing Linux build in then reimplement it all in TypeScript", "excerpt": "> Well, there it is, the dumbest thing I'll read on the internet all week. Rude. In case you're open to learning, here's why I think this is useful. The big lesson we've learned from Claude Code, Codex CLI et al over the past twelve months is that the most useful tool you can provide to an LLM is Bash. Last year there was enormous buzz around MCP - Model Context Protocol. The idea was to provide a standard for wiring", "context": "", "use_case": "", "switched_from": "", "story": "JSLinux Now Supports x86_64"}, {"id": 754672496, "item_id": 47167031, "url": "https://news.ycombinator.com/item?id=47167031", "by": "gaigalas", "date": "2026-02-26", "version": null, "stance": "warn", "quote": "That's a lot of incompatibilities.", "excerpt": "https://github.com/vercel-labs/just-bash/blob/main/src/spec-tests/bash/KNOWN_LIMITATIONS.md That's a lot of incompatibilities. LLMs like to use the shell because it's stable and virtually unchanged for decades. It doesn't need to worry much about versions or whether something is supported or not, it can just assume it is. Re-implementing bash is a herculean effort. I wish good luck.", "context": "", "use_case": "bash-compatible shell for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}]}], "who": [], "tags": [], "use_cases": ["bash for agents", "running bash in js runtime", "virtual bash for ai agents", "sandboxed cli and file ops", "virtual bash for agents", "bash sandbox for agents"], "compared": [], "makers": [{"id": 754675584, "item_id": 47167224, "url": "https://news.ycombinator.com/item?id=47167224", "by": "huntaub", "date": "2026-02-26", "version": null, "stance": "recommend", "quote": "We just released a driver that allows users of just-bash to attach a full Archil file system", "excerpt": "We just released a driver that allows users of just-bash to attach a full Archil file system, synced to S3. This would let you run just-bash in an enrivonment where you don't have a full VM and get high-performance access to data that's in your S3 bucket already to do like greps or edits. Check it out here: https://www.npmjs.com/package/@archildata/just-bash", "context": "", "use_case": "running shell for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}], "threads": [{"url": "https://news.ycombinator.com/item?id=47165648", "title": "just-bash: Bash for Agents", "mentions": 8}, {"url": "https://news.ycombinator.com/item?id=46824877", "title": "Show HN: Amla Sandbox \u2013 WASM bash shell sandbox for AI agents", "mentions": 2}, {"url": "https://news.ycombinator.com/item?id=50132911", "title": "Tsc-ts: TypeScript written in TypeScript", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=48845364", "title": "Files over tools: how we built our agent with a virtual filesystem and bash", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=47741527", "title": "Ask HN: What Are You Working On? (April 2026)", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=47311484", "title": "JSLinux Now Supports x86_64", "mentions": 1}], "sentiment_by_month": {"2025-11": {}, "2025-12": {}, "2026-01": {"neutral": 1, "recommend": 1}, "2026-02": {"compare": 2, "warn": 1, "neutral": 3, "recommend": 2}, "2026-03": {"recommend": 1, "neutral": 1, "warn": 1}, "2026-04": {"neutral": 1}, "2026-05": {}, "2026-06": {}, "2026-07": {"neutral": 1}, "2026-08": {}, "2026-09": {}, "2026-10": {"neutral": 1}}, "versions": [], "version_unnamed": 0, "family_ref": null, "runs_on": null, "lines": [], "quotes": [{"id": 802139792, "item_id": 50133737, "url": "https://news.ycombinator.com/item?id=50133737", "by": "tallowen", "date": "2026-10-17", "version": null, "stance": "neutral", "quote": "See just bash as another example project for taking advantage of this", "excerpt": "The back and forth between writing tools in javascript and go or rust seems like it's in an unstable equilibrium right now: - Go / Rust: It's easier than ever to rewrite existing tools in more performand languages - Javascript: The v8 runtime for vercel or cloudflare workers is a much cheaper way to run certain workloads (e.g. conversational agents) than running a heavy weight vm. See just bash as another example pro", "context": "", "use_case": "running bash in JS runtime", "switched_from": "", "story": "Tsc-ts: TypeScript written in TypeScript"}, {"id": 781569440, "item_id": 48848090, "url": "https://news.ycombinator.com/item?id=48848090", "by": "andai", "date": "2026-07-09", "version": null, "stance": "neutral", "quote": "A virtual bash environment with an in-memory filesystem, written in TypeScript and designed for AI agents.", "excerpt": "I thought it would be bash+fuse but it's actually running in the matrix: simulated bash in Elixir ported from Vercel's just-bash: > A virtual bash environment with an in-memory filesystem, written in TypeScript and designed for AI agents. >Broad support for standard unix commands and bash syntax with optional curl, Python, JS/TS, and sqlite support. https://github.com/vercel-labs/just-bash/tree/main/packages/just-bas", "context": "", "use_case": "virtual bash for AI agents", "switched_from": "", "story": "Files over tools: how we built our agent with a virtual filesystem and bash"}, {"id": 763926018, "item_id": 47745376, "url": "https://news.ycombinator.com/item?id=47745376", "by": "buremba", "date": "2026-04-12", "version": null, "stance": "neutral", "quote": "uses just-bash with pi", "excerpt": "I'm working on multi-tenant version of OpenClaw for organizations that has shared memory layer. It includes an entity based agent context layer that can be used as OpenClaw plugin and a sandbox runtime layer which uses just-bash with pi and let you expose the context via a bot an API. https://lobu.ai", "context": "", "use_case": "", "switched_from": "", "story": "Ask HN: What Are You Working On? (April 2026)"}, {"id": 757161474, "item_id": 47322592, "url": "https://news.ycombinator.com/item?id=47322592", "by": "simonw", "date": "2026-03-10", "version": null, "stance": "warn", "quote": "I'd rather run a 10MB WASM bundle with a full existing Linux build in then reimplement it all in TypeScript", "excerpt": "> Well, there it is, the dumbest thing I'll read on the internet all week. Rude. In case you're open to learning, here's why I think this is useful. The big lesson we've learned from Claude Code, Codex CLI et al over the past twelve months is that the most useful tool you can provide to an LLM is Bash. Last year there was enormous buzz around MCP - Model Context Protocol. The idea was to provide a standard for wiring", "context": "", "use_case": "", "switched_from": "", "story": "JSLinux Now Supports x86_64"}, {"id": 756946242, "item_id": 47309140, "url": "https://news.ycombinator.com/item?id=47309140", "by": "capevace", "date": "2026-03-09", "version": null, "stance": "neutral", "quote": "just-bash.dev", "excerpt": "https://struktur.sh An all-in-one tool for structured data extraction with LLMs. $ struktur extract \u2014input doc.pdf \u2014schema schema.json \u2014model openai/gpt-5 - can prepare documents (PDF->text etc.) - run multiple different extraction strategies - runs a full agent loop for data extraction in-process using Pi agent and just-bash.dev. It can grep through large files for example.", "context": "", "use_case": "", "switched_from": "", "story": "Ask HN: What Are You Working On? (March 2026)"}, {"id": 755363601, "item_id": 47210225, "url": "https://news.ycombinator.com/item?id=47210225", "by": "goodmodule", "date": "2026-03-01", "version": null, "stance": "recommend", "quote": "For CLI and file operations we have Vercel's just-bash", "excerpt": "I somehow agree with this but want to add my two cents here. Cloudflare's Codemode[0] is a great \"replacement\" for MCP because AI is trained for writing code and handling errors. But it also doesn't fix security and sandboxing. For CLI and file operations we have Vercel's just-bash[1] but for everything else there is no safe solution. Therefore MCP still makes sense until somebody sandboxes this part as well without ", "context": "", "use_case": "Sandboxed CLI and file ops", "switched_from": "", "story": "MCP is dead. Long live the CLI"}, {"id": 754858865, "item_id": 47178679, "url": "https://news.ycombinator.com/item?id=47178679", "by": "thoughtfulchris", "date": "2026-02-27", "version": null, "stance": "recommend", "quote": "I love the approach of just bash as well. Super cool!", "excerpt": "I'm hacking on a similar thing that lets you build CLIs directly into xterm / ghostty web so that they also work in the terminal. Eg they are cross platform web and CLI. Demo: https://wizard-nine-blush.vercel.app/ Project: https://ink-web.dev I love the approach of just bash as well. Super cool! Edit: warning - don't use it mobile.", "context": "", "use_case": "bash for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754756368, "item_id": 47172273, "url": "https://news.ycombinator.com/item?id=47172273", "by": "rbbydotdev", "date": "2026-02-26", "version": null, "stance": "recommend", "quote": "It\u2019s cool to see this project and others pop up.", "excerpt": "It\u2019s cool to see this project and others pop up. Virtualizing os primitives like bash and even file systems You can interface around the nodejs files system interface and have access to some nice tools, like git isomorphic for instance. Then obviously everything couples nicely with agents. Something I did in my markdown editor project: https://github.com/rbbydotdev/opal Have half a mind to release a browser kit which", "context": "", "use_case": "virtual bash for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754728176, "item_id": 47170511, "url": "https://news.ycombinator.com/item?id=47170511", "by": "rob", "date": "2026-02-26", "version": null, "stance": "neutral", "quote": "Web UI for it: https://justbash.dev", "excerpt": "Web UI for it: https://justbash.dev", "context": "", "use_case": "Bash sandbox for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754691249, "item_id": 47168203, "url": "https://news.ycombinator.com/item?id=47168203", "by": "jeffchuber", "date": "2026-02-26", "version": null, "stance": "neutral", "quote": "plugs into just-bash", "excerpt": "last weekend I vibe-coded a project called `openfs` that plugs into just-bash https://github.com/jeffchuber/just-bash-openfs it puts a bash interface in front of s3, filesystem (real and in-memory), postgres, and chroma. still very much alpha - but curious what people think about it. see an example app here: https://github.com/jeffchuber/openfs-incident-app", "context": "", "use_case": "Bash for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754679088, "item_id": 47167443, "url": "https://news.ycombinator.com/item?id=47167443", "by": "RobertLong", "date": "2026-02-26", "version": null, "stance": "compare", "quote": "I love the concept but isn\u2019t this incredibly slow compared to native cli tools?", "excerpt": "This ends up reading files into node.js and then running a command like grep but implemented in JS. I love the concept but isn\u2019t this incredibly slow compared to native cli tools? Building everything in JS on top of just readFile and writeFile interfaces seems pretty limited in what you can do for performance.", "context": "", "use_case": "bash for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754675488, "item_id": 47167218, "url": "https://news.ycombinator.com/item?id=47167218", "by": "IceWreck", "date": "2026-02-26", "version": null, "stance": "neutral", "quote": "At this point why not make the agents use a restricted subset of python, typescript or lua", "excerpt": "At this point why not make the agents use a restricted subset of python, typescript or lua or something. Bash has been unchanged for decades but its not a very nice language. I know pydantic has been experimenting with https://github.com/pydantic/monty (restricted python) and I think Cloudflare and co were experimenting with giving typescript to agents.", "context": "", "use_case": "", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 754672496, "item_id": 47167031, "url": "https://news.ycombinator.com/item?id=47167031", "by": "gaigalas", "date": "2026-02-26", "version": null, "stance": "warn", "quote": "That's a lot of incompatibilities.", "excerpt": "https://github.com/vercel-labs/just-bash/blob/main/src/spec-tests/bash/KNOWN_LIMITATIONS.md That's a lot of incompatibilities. LLMs like to use the shell because it's stable and virtually unchanged for decades. It doesn't need to worry much about versions or whether something is supported or not, it can just assume it is. Re-implementing bash is a herculean effort. I wish good luck.", "context": "", "use_case": "bash-compatible shell for agents", "switched_from": "", "story": "just-bash: Bash for Agents"}, {"id": 750110736, "item_id": 46881921, "url": "https://news.ycombinator.com/item?id=46881921", "by": "skybrian", "date": "2026-02-03", "version": null, "stance": "compare", "quote": "I haven't tried just-bash, but it seems interesting for comparison", "excerpt": "If it's a coding agent, it will need to be able to write scripts and run them. I haven't tried just-bash, but it seems interesting for comparison: https://github.com/vercel-labs/just-bash", "context": "", "use_case": "", "switched_from": "", "story": "Show HN: Sandboxing untrusted code using WebAssembly"}, {"id": 749264768, "item_id": 46829048, "url": "https://news.ycombinator.com/item?id=46829048", "by": "simonw", "date": "2026-01-30", "version": null, "stance": "recommend", "quote": "Sounds like just-bash:", "excerpt": "Sounds like just-bash: https://github.com/vercel-labs/just-bash", "context": "", "use_case": "", "switched_from": "", "story": "Show HN: Amla Sandbox \u2013 WASM bash shell sandbox for AI agents"}, {"id": 749221298, "item_id": 46826331, "url": "https://news.ycombinator.com/item?id=46826331", "by": "vimota", "date": "2026-01-30", "version": null, "stance": "neutral", "quote": "built on just-bash, AgentFS, and Pyodide", "excerpt": "Sharing our version of this built on just-bash, AgentFS, and Pyodide: https://github.com/coplane/localsandbox One nice thing about using AgentFS as the VFS is that it's backed by sqlite so it's very portable - making it easy to fork and resume agent workflows across machines / time. I really like Amla Sandbox addition of injecting tool calls into the sandbox, which lets the agent generated code interact with the harn", "context": "", "use_case": "", "switched_from": "", "story": "Show HN: Amla Sandbox \u2013 WASM bash shell sandbox for AI agents"}]}