IP maximalism is the present zeitgeist but that’s just how knowledge flows.
Open source is not IP maximalist by any means. I am merely asking that the appropriate credit be provided.
Written about it here before: https://wiki.roshangeorge.dev/w/Blog/2026-09-08/Intellectual...
It isn’t something I care very much about, except when it’s used as a certificate of achievement. I almost never do literature searches with an attempt to dedupe. I only ever do it to see if someone has explored something better than I have. That’s often the case but other times it is not.
The first step in approaching anything difficult is seeing whether someone else has already solved it.
I agree that there will be cases where you implement tricks that others have had before you, without knowing. A few years ago, I had a delightful idea, experimented and wrote it up. One commenter directed me to a post that described it as "folk knowledge". There will be other cases where you encountered an idea before, but didn't remember it.
Still, crediting what you can easily know you cited is good. Even aside from credit, comparisons to existing systems are part of how we understand what a system does.
- https://www.anthropic.com/engineering/a-postmortem-of-three-...
- https://www.anthropic.com/engineering/how-we-contain-claude
That's how the knowledge that it was a facsimile was lost.
What is douchey is presenting the whole thing as some sort of intense novelty and stroke of genius required in the age of agents when it's just doing what the other BigCo companies did to scale their monorepos already. Like a decade (or more) ago.
The reality it is when I first read the thing I was -- as a Xoogler -- like "Oh, yeah, so, like Piper & SrcFs and the stuff that Meta also does" and really didn't understand why they wouldn't have started with something off the shelf inside of vibe-conjuring a clone that they would then have to support
To me it speaks ill, again, of the engineering culture at Anthropic. "We do these things not because they are useful, but because they are novel."
Don't they have better things to do at Anthropic than building their own source control or rewriting Bun from scratch in another language? Like, y'know, basic site reliability? Or a coding harness that doesn't eat multiple GB of RAM?
Google's isn't open source. Meta's is an option, any others you would consider?
Even Google started with Perforce originally and only forked/rebuilt when it stopped being able to scale. And did so in a very incremental fashion.
You can write it, but can you maintain it? Can you even fully understand what was built? Can you staff the team to manage the bugs? The potential data loss?
If you're using Anthropic's recently-announced plagiarized source control system as your proof that this is possible, then, well, it's still not possible. That system was not built from scratch, and we both know that you were informed roughly four hours before posting this comment that the folks involved with this have been directly informed of that fact. You even called the failure of Anthropic to acknowledge that this was not a from-scratch project and to credit the project from which they lifted the design that they would have had to pour a lot of time and effort into to replicate -and I quote- "a scandal".
We've since got a few more details, it looks like the new information is that there are people on the team who built Scion who had previously worked at Meta and had direct experience with Sapling and Mononoke: https://sunshowers.io/posts/anthropic-mononoke-2/
I stand by my original comment: back when Google built their version of this it wasn't possible for a team of seven to use LLMs to build a new custom implementation in five months that incorporated existing patterns (in a way that some people would classify as cheating / plagiarism / insert-your-criticism-here).
A quick look around tells us that Mononoke came from Facebook nine years ago. [0][1] Similarly, Piper was built long before LLMs were more than -at best- some very small scale implementations.
Git was started in 2005. IIRC, it went from a blank editor window and some ideas in Torvalds's head to self-hosting in four days and managing the code for the then-latest Linux kernel release in two months. As I understand it, project staffing was also low; somewhere between one and a handful of people. Such amazing velocity and tiny staff size! <strike>Impossible without LLMs!</strike>
I also note that you've weakened your claim from "build a new system from scratch" to "build a new custom implementation ... that incorporated existing patterns". [3]
> Here's the context for that "scandal" comment...
Yes, that's the conversation that I wrote about. The rather unflattering start to that thread that you linked is important context [2], and the blog post you link to talks about the behavior you called "a scandal". I read all of the discussion for the first report, and most of it for the second.
> I stand by my ["]original["] comment...
Like many folks have mentioned to in recent months, occasionally saying "Jeez, that behavior is awful. Yeah, that's inexcusable." doesn't mean anything when you're back at bat for these companies a few hours later.
[0] <https://github.com/facebookarchive/mononoke>
[1] <https://news.ycombinator.com/item?id=16565299>
[2] <https://lobste.rs/c/wk6js5>
[3] The following paragraph from 'anthropic-mononoke-2' seems particularly apropos in light of how you've shifted your claim since I objected to it:
*This makes Anthropic’s achievement significantly less impressive.* Anyone who’s put a distributed system into production knows how many issues tend to crop up during the productionizing process. “Our LLM built this thing, productionized it, and dealt with all the attendant challenges over 5 months” is a significantly more compelling narrative than “the source control team at Meta had spent 10 years building and productionizing this system, and we were able to point our LLM at it and rebuild it in 5 months”.Others read it and interpreted it as "a team of seven engineers designed this software and used a Claude to build it".
The former group seem a whole lot more outraged by this situation than the latter. Which interpretation did you take from Anthropic's post?
Neither. Anthropic originally claimed the same thing that you originally did in this thread; that this was a from-scratch implementation, and that the use of LLM-based tools was the primary reason they could go from zero to a nontrivial version control system in ~five months.
Please stop going to bat for these folks.