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We replaced RAG with a virtual filesystem for our AI documentation assistant

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Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#171
> At 850,000 conversations a month, even a minimal setup (1 vCPU, 2 GiB RAM, 5-minute session lifetime) would put us north of $70,000 a year

Am I crazy or is 850,000/month of anything...not really that much? Where are you spending all your CPU cycles and memory usage?

> ChromaFs is built on just-bash by Vercel Labs (shoutout Malte!), a TypeScript reimplementation of bash that supports grep, cat, ls, find, and cd

Oh.. I see.

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#172

Earlier quoted context omitted.

Honestly, just from this question, I think you know enough that I’d go spend $20/month for a subscription to Codex, Claude Code, or Cursor, and ask them to teach you all this. I bet if you put in your comment verbatim with Opus 4.6 and went back and forth a bit, it could help you figure out exactly what you need and build a first version in a couple hours. Seriously, if you know the fundamentals and can poke and prod…

> Honestly, just from this question, I think you know enough that I’d go spend $20/month for a subscription to Codex, Claude Code, or Cursor, and ask them to teach you all this. Paying $20/m sounds like overkill. I have tabs open for all of the most well-known AI chatbots. Despite trying my hardest, it is not possible to exhaust your free options just by learning. Hell, just on the chatbots alone, small projects can…

Yeah, but when it comes to actually building stuff, using Codex is night and day different from using ChatGPT.

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#173

The real thing I think people are rediscovering with file system based search is that there’s a type of semantic search that’s not embedding based retrieval. One that looks more like how a librarian organizes files into shelves based on the domain. We’re rediscovering forms of in search we’ve known about for decades. And it turns out they’re more interpretable to agents. https://softwaredoug.com/blog/2026/01/08/seman…

Exactly. Traditional library science truly captured deep patterns of information architecture.

https://x.com/wibomd/status/1818305066303910006

Pixar got this right in Ralph Wrecks The Internet.

https://x.com/wibomd/status/1827067434794127648

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#174
post #171

> At 850,000 conversations a month, even a minimal setup (1 vCPU, 2 GiB RAM, 5-minute session lifetime) would put us north of $70,000 a year Am I crazy or is 850,000/month of anything ...not really that much? Where are you spending all your CPU cycles and memory usage? > ChromaFs is built on just-bash by Vercel Labs (shoutout Malte!), a TypeScript reimplementation of bash that supports grep, cat, ls, find, and cd Oh.…

If you give every agent an isolated container to use, you’re going to be paying for the reserved memory while the container is active, even if the agent isn’t doing anything.

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#175
RAG provided me no way to read the content myself. I now integrate the knowledge into a static page that I can read and edit myself in Markdown. Similar to MkDocs. But after I edit the content or remove elements that are no longer true, I build a JSON file and tell the agent how to query this source.

python -c " import json, wire, pathlib d = json.loads((pathlib.Path(wire.__file__).parent / 'assets/search_index.json').read_text()) [print(e['title'], e['url']) for e in d if 'QUERY' in (e.get('body','') + e.get('title','')).lower()] "

python -c " import json, wire, pathlib d = json.loads((pathlib.Path(wire.__file__).parent / 'assets/search_index.json').read_text()) [print(e['body']) for e in d if e.get('url','') == 'PATH'] "

https://wire.wise-relations.com/use-cases/replace-rag/

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#176
post #75

This is one of the most confusing claims I've seen in a long time. Grep and others over files would be the equivalent of an old fashioned keyword search where most RAG uses vector search. But everything else they claim about a file system just suggests that they don't know anything about databases. I'm not familiar with how most out of the box RAG systems categorize data, but with a database you can index content lit…

Also odd in that most filesystems implement directories and file names as...a database. You can use a filesystem as a database but you're not being as clever as you thought.

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#178

Earlier quoted context omitted.

> Honestly, just from this question, I think you know enough that I’d go spend $20/month for a subscription to Codex, Claude Code, or Cursor, and ask them to teach you all this. Paying $20/m sounds like overkill. I have tabs open for all of the most well-known AI chatbots. Despite trying my hardest, it is not possible to exhaust your free options just by learning. Hell, just on the chatbots alone, small projects can…

Yeah, but when it comes to actually building stuff, using Codex is night and day different from using ChatGPT.

> Yeah, but when it comes to actually building stuff, using Codex is night and day different from using ChatGPT.

Sure, but that wasn't what you recommended Codex for, was it?

>>> Honestly, just from this question, I think you know enough that I’d go spend $20/month for a subscription to Codex, Claude Code, or Cursor, and ask them to teach you all this.

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#179
post #169
post #168

We use both a virtual file system and RAG — they each excel in different areas. The trick with RAG is the quality of data: we use an LLM to chunk into semantically cohesive sections, as well as generate metadata (including fact triples and links to other related chunks in the document) for every chunk as well as the document as a whole. We use voyage contextual embeddings to then embed each chunk with the document an…

Our vfs is also pretty powerful too, though: it is all backed by postgres then projected into files/directories for our agents. They get basic grep etc but also optimized fts tools for bm25, jq, and preview tools that show representative slices of large documents. All on top of Pydantic AI.

hey i tried to check out your website but i'm getting cloudflare error page code 520

Re: We replaced RAG with a virtual filesystem for our AI documentation assistant

#180

But SQLite is notoriously 35% faster than the filesystem [0], so why not use that? [0] https://news.ycombinator.com/item?id=14550060

SQLite + GPT5.4 works very well for me. My biggest success is a Roslyn method that takes a .NET solution and converts it into a SQLite database with Files, Lines, Symbols, and References tables. I've found this approach to perform substantially better than a flat, file-based setup (i.e., like what Copilot provides in Visual Studio). Especially, for very large projects. 100+ megs of source is no problem. The relationa…

Interesting... what is the use case for the AI that is querying it? Is it how to develop additional features for integration with your app or do you have some other use case? Code review/audit/debugging/etc. For AI developing against an API I would think an OpenAPI json file would do the trick.

Is the Roslyn method called as part of the build/publish?

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