I used AI to build a music recommender system that itself uses no AI in its operation.

I have been promoting the system in communities that can sometimes be considerably anti-AI. But people usually assume that it is AI because, well, it's a recommender system.

Anyways, after a 30-year break, I rebuilt it and got it working the way I always wanted! It basically uses the same 10 lines of code, (for which I was granted now-expired US patent #5749081), but with a good interface around it instead of a lousy 1990s one.

You tell it your 5 favorite albums, and it recommends other albums to try.

It uses collaborative filtering (CF) to generate the music recommendations. It's just now exiting the "cold start" phase that all CF systems have to get through.

The tagline I use is: "No sign-up needed, instant results, takes 2 minutes to try. Not AI."

Try it here:

[https://SimilaritiesEngine.com](https://similaritiesengine.com/)

If you're curious, here's a New York Times article from way back then. (But the URL in the article is wrong, so if you go read it, come back here to try the new version, alive and working):

https://archive.nytimes.com/www.nytimes.com/library/cyber/0101miracolumn.html

The system is about 6,000 lines of code, vibe-coded by me using Claude Code. I have basically never looked at a line of the source. (But I have a part-time partner now who is hand-revising some code.)

Up until now, I have publicized the site mostly on Reddit. Boy, did I catch grief there for it "being an AI system."

At first, I got Claude's help on the language for some of the website copy and some of my Reddit posts.

I mostly stopped getting downvoted for it being AI once I learned my lesson (in "The Great r/Vinyl Debacle," https://www.reddit.com/r/vinyl/comments/1ul7o7c/i_built_a_music_recommender_in_1996_that_only/ ), which led me to tell Claude "Never use em dashes in anything, anywhere, that you help me with!" (To be fair, the downvotes made the post controversial and drove views to 15K, but my actual URL got buried.)

You could argue that my "no AI" claim isn't fully true, and that I should instead say something like "no LLMs or generative AI are in the product itself, just classic collaborative filtering." But what I tell people sometimes is this: The weights file behind a SOTA AI system like Claude Fable is, by some estimates, 2 TB or more. The equivalent file in my system (my graph database or "links" table) is about 3 MB in size right now.

So my question for Hacker News is: how often do you hide the fact that AI was involved in the production of your product?

I actually think, based on some of the things I have seen in the press and on discussions I have had with people, that acquaintances might be talking behind my back in an "oh he's heavily into AI so you should not trust him" sort of way. Yeah, saying that makes me sound crazy. Am I crazy?

Details on the tech (Cloudflare, D1, etc.) can be found on the website too.