CODA now has a released page.

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Graham Banks
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Re: CODA now has a released page.

Post by Graham Banks »

AndrewGrant wrote: Tue Jul 14, 2026 2:35 am
I will summarize again the most straight-forward argument, since it seems some posters are having a hard time following the conversation.

- Coda recently changed the license to GPLv3.
- Coda contains code from Reckless and Viridithas.
- Reckless and Viridithas are licensed under the AGPLv3.
- The GPLv3 is not compatible with the AGPLv3, as it rescinds some obligations.
- By publishing AGPLv3'ed code, marked as GPLv3 code, Coda is attempting to re-license Reckless/Viridithas.
At least, the Coda co-author is prepared to address all of these concerns.
I guess once that's been done, you'll have no beef with Coda?
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AndrewGrant
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Re: CODA now has a released page.

Post by AndrewGrant »

Graham Banks wrote: Tue Jul 14, 2026 2:46 am
AndrewGrant wrote: Tue Jul 14, 2026 2:35 am
I will summarize again the most straight-forward argument, since it seems some posters are having a hard time following the conversation.

- Coda recently changed the license to GPLv3.
- Coda contains code from Reckless and Viridithas.
- Reckless and Viridithas are licensed under the AGPLv3.
- The GPLv3 is not compatible with the AGPLv3, as it rescinds some obligations.
- By publishing AGPLv3'ed code, marked as GPLv3 code, Coda is attempting to re-license Reckless/Viridithas.
At least, the Coda co-author is prepared to address all of these concerns.
I guess once that's been done, you'll have no beef with Coda?
If Coda can find a license that is compatible with all the engines digested, and then package releases with the appropriate licenses/notices, then I have no problem with Coda in particular. Adam is very clearly not a malicious actor in any way. His project just happens to be at the center of the broader conversation about LLMs and Licensing, since he is the first guy to make a serious effort in the computer-chess space.

I have no "conquest" against Coda specifically -- in contrast to the conquest against Fire/Houdini.
Some users here have suggested otherwise, but they have misread or misinterpreted my motivations.
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jasper.sinclair
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Re: CODA now has a released page.

Post by jasper.sinclair »

AndrewGrant wrote: Tue Jul 14, 2026 3:05 am I have no "conquest" against Coda specifically -- in contrast to the conquest against Fire/Houdini.
Some users here have suggested otherwise, but they have misread or misinterpreted my motivations.
your 'conquest' ? yes I see where you're coming from, comparing yourself to...
https://en.wikipedia.org/wiki/Spanish_c ... tec_Empire :shock:
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jasper.sinclair
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Re: CODA now has a released page.

Post by jasper.sinclair »

I'm a bit curious as to why you have only responded to "Ethereal's syzygy.c is not an original implementation"

Does the ethereal chess engine use any code and/or ideas from stockfish? Looking for a short and concise answer, not an extensive analysis.
ChatGPT: "Yes. Ethereal uses both ideas and some code from Stockfish (along with other open-source engines). It is an independently developed engine overall, but it has incorporated Stockfish-derived techniques and some GPL-compatible code where appropriate."
Can you be a little more specific?
ChatGPT: "Syzygy probing in Ethereal is derived from Ronald de Man's Syzygy probing code, just as in Stockfish. That's explicitly acknowledged.
Over the years, Andrew Grant has also imported specific search heuristics from Stockfish (LMR formulas, pruning tweaks, etc.), but those are often reimplemented rather than pasted.
There are utility components where the line between "rewrite" and "copy" is much blurrier. Some small modules are essentially the same design with C syntax instead of C++.

So the statement "Ethereal contains no Stockfish code" would be stronger than the evidence supports. The more accurate statement is:

Ethereal is an independently developed engine overall, but it has incorporated some code and many implementation techniques from other open-source engines, including Stockfish, under the GPL."
Can you give an example of code directly copied from Stockfish or any other engine?
ChatGPT: "Yes. One clear example is Syzygy tablebase probing.

Ethereal's syzygy.c is not an original implementation—it wraps Pyrrhic, which is itself a fork of Fathom, Ronald de Man's GPL Syzygy probing library that originated from the Stockfish ecosystem. Ethereal explicitly includes and interfaces with Pyrrhic rather than reimplementing the probing logic from scratch.

Another example, according to Andrew Grant himself, is:

Windows NUMA support, which he says was taken from Texel/Brainfish. He also states that, aside from Pyrrhic and this NUMA code, Ethereal does not explicitly use external source code.

So, if you're looking for direct code reuse rather than just ideas:

✅ Syzygy probing (via the Pyrrhic/Fathom codebase).
✅ Windows NUMA code (from Texel/Brainfish).

For Stockfish search code specifically, there isn't a publicly acknowledged example of a file that is simply copied wholesale. Most of the Stockfish influence there is in algorithms and heuristics rather than verbatim source code."
I'm sure many here would be interested your 'spin' on the facts above :shock: , as well as you dubious and confusing take on licenses...of course we all know you're a licensing genius! no disprespect intended!
Last edited by jasper.sinclair on Tue Jul 14, 2026 4:01 am, edited 1 time in total.
AndrewGrant
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Re: CODA now has a released page.

Post by AndrewGrant »

jasper.sinclair wrote: Tue Jul 14, 2026 3:50 am I'm a bit curious as to why you have only responded to "Ethereal's syzygy.c is not an original implementation"
I started here, because it was easy to refute, as ChatGPT had made a mistake in the license.

Do you acknowledge that ChatGPT was mistaken to suggest the Pyrrhic/Fathom are under GPLv3?
And do you acknowledge that Ethereal is not violating anyone's copyright as it pertains to Pyrrhic/Fathom?

If you can acknowledge that, then we could start to discuss additional points of interest/concern.
But if we can't acknowledge this, then I don't see the point of trying to argue further. And we're also off-topic, and needing a new thread.

Edit:
Disappointing to see that you edited your post, to add a personal attack at the end. No reason for that.
The information I am conveying about licenses is something you could ask your LLM to explain as well.
I'm not offering novel legal takes here. This is all very textbook.