Sudoku·AD – free variant sudoku player with technique-based hints (feedback welcome)

[sudokuad]

Hello everyone. Sorry for writing in English; replies in German are very welcome.

I'm Hussain, and for the past months I've been building Sudoku·AD (https://sudoku.ad/?utm_source=logicmaste...tent=forum), a free browser player for classic and variant sudoku. It has no ads, and you don't need an account.

It covers 32 variant types (thermo, arrow, killer, kropki, whispers, sandwich, renban and more). The hints name the technique each step needs and explain it. There are 14 technique guides, a daily puzzle and a setting tool.

To be clear about where puzzles come from: about 2,000 are from my own generator, which checks that the variant constraints are needed for a unique solution (I won't put those on the Rätselportal, since it's for handcrafted puzzles). The rest, about 18,000, are puzzles by around 1,350 setters, most of them first published here on the Rätselportal. Each one shows the setter's name, a link back to the original and a note that the puzzle belongs to its setter.

For setters: if you'd rather your puzzles weren't on sudoku.ad, reply here, send me a PM, or email hello@sudoku.ad, and they come down the same day, no questions asked. At https://sudoku.ad/setters/?utm_source=lo...tent=forum you can see everything the site has of yours and approve or decline each puzzle. If credit or a link is wrong anywhere, tell me and I'll fix it.

I'd especially value feedback on two things: whether the hint explanations match how you'd actually solve, and whether any rule text is worded differently from how this community writes it.

Thank you for reading, and for everything this forum and the portal have done for the hobby.

[CHalb]

In your list of setters I find among others the following nicks from the portal:
DocLogic, Richard, Florian Wortmann, RobertBe, ThePedallingPianist, Phistomefel, glim_hippo, juggler, CJK

And I see names, e.g.:
Christoph Seeliger, Philipp Blume

Have you asked any or some of them before using their Sudokus or is your post here your first contact offer to them?

[CHalb]

And a feedback: At least on my cell phone the puzzle https://logic-masters.de/Raetselportal/R...?id=0002LC (24 Rätsel in 24 Stunden (Teil 4) - Doppelstern by Zzzyxas) does not appear correctly in your app.

It is not shown completely (maybe there is some way to scroll I haven't figured out).
There are a cage, a mark in the middle and an outside clue, which are not part of the original puzzle.
It is categorised as Variant Sudoku 9x9. It is not 9x9. And although a solved Starbattle has same symbols in row/column/area I'd not declare it as Sudoku.

[uvo]

IANAL: This is a massive copyright violation and might get you in a lot of trouble. And no, opt-out for puzzle authors is not sufficient.

[sudokuad]

No, we didn't, and that was wrong. I'm sorry. Most of these puzzles went up while we were testing and debugging the player and the import, and we should have kept them private until each setter had agreed. Today we're taking every puzzle off the public site unless its setter has said yes. That covers the setters you listed and everyone else. They'll only be listed again if a setter asks us to.

From the Sudoku·AD team

[sudokuad]

IANAL: This is a massive copyright violation and might get you in a lot of trouble. And no, opt-out for puzzle authors is not sufficient.

Point taken, and thank you for being direct. Opt-out wasn't enough, so we're switching to opt-in from today. Any puzzle whose setter hasn't agreed is coming off the public site, including listings, search and the sitemap. Players can still paste a link to any puzzle and solve it in their own private library. Those copies are never public, and they credit the setter and link to the original.

We'd value your advice. What's the right way to reach setters here and ask first? Is a private message on the forum fine, or would you suggest something else?

From the Sudoku·AD team

[DiMono]

IANAL: This is a massive copyright violation and might get you in a lot of trouble. And no, opt-out for puzzle authors is not sufficient.

Point taken, and thank you for being direct. Opt-out wasn't enough, so we're switching to opt-in from today. Any puzzle whose setter hasn't agreed is coming off the public site, including listings, search and the sitemap. Players can still paste a link to any puzzle and solve it in their own private library. Those copies are never public, and they credit the setter and link to the original.

We'd value your advice. What's the right way to reach setters here and ask first? Is a private message on the forum fine, or would you suggest something else?

From the Sudoku·AD team

First of all, thank you for taking down the puzzles you don't have clearance for. Note that there is a difference between deleting them and hiding them. For example, the creator page for DiMono still says there are 68 puzzles, it just doesn't show them. I imagine other people's creator pages will be similar. All else aside, this will be confusing for any visitors to the website who want to see if their favourite setter has any puzzles there.

I scanned through those 68 puzzles while they were still displayed, and there appears to be a problem with your scraping tool (does LMD allow scraping?). I only have 60 puzzles posted to LMD, so when I saw 68 listed under my name I became concerned that you may have taken paywalled puzzles. It turns out you actually got some puzzles twice. Sometimes the two instances had the same title, and sometimes the titles were slightly different. It also listed Taco Bowl 3 as "medium" in one instance, which is funny, but also very much not the case.

Finally, while I understand the idea behind letting a setter claim their setter page, is there anything in place to make sure people don't claim other people's pages? Could someone else claim my setter page and pretend to be me on your site? What authentication process do you have to make sure people are who they say they are when claiming a page? Impersonation is a big problem online, so if you aren't already taking measures to prevent that, you should do so.

[sudokuad]

Follow-up: hiding wasn't enough, as DiMono said. As of today (Nov 3), every puzzle and all setter data from anyone who hadn't given permission has been fully deleted from sudoku.ad and all our servers. That covers puzzles, setter names, setter pages and counts, so it's gone, not hidden. We no longer pull anything from LMD, and the site is opt-in only.

On scraping: we didn't have LMD's permission, and that was wrong. On setter pages: with no outside setters listed, there's nothing to claim. Any future opt-in will be confirmed directly with the setter through their LMD PM or email before anything is shown.

If anyone wants a personal confirmation, email hello@sudoku.ad. Sorry again, and thanks for holding us to it.

Hussain