Like you said, in the AI space a pre-print on arXiv is massively more likely than anything that's been through peer-review.

I called it a paper here because it's by people with an academic affiliation and is of comparable quality (if not better than) many of the other "papers" we see.

I also like it when a paper isn't a PDF. PDFs are a bad way of communicating information.

(I will note that the authors themselves didn't call it a paper, their own BibTeX reference calls it a "blog post":)

  @misc{takehi2026weightspace,
    title        = {{Sparks of Weight-Space Programming: LLMs can natively read \& write neural network weights}},
    author       = {Takehi, Rikiya and Teoh, Jayden and Zhang, Alex and Khattab, Omar},
    year         = {2026},
    month        = nov,
    howpublished = {\url{https://rikiyat.github.io/blog/weight-space-programming/}},
    note         = {Blog post}
  }