Flaming Durtles App Broke My Wanikani

Possibly due to a new update with Wanikani(?) there’s been a desync between Flaming Durtles and desktop Wanikani in which five words exist on the desktop app that don’t exist on the Flaming Durtles app. Finishing those lessons on desktop has caused my lessons to be irreparably counted as “NaN”, and whenever I do reviews, every time I finish a word I am disconnected from WaniKani and forced to reconnect to continue my reviews.

How can I fix this issue?

Try Smoldering Durtles.


Thank you, but how will I fix the damage done to the desktop version of Wanikani? Will Smoldering take care of that?

Thanks again for the recommendation, and sorry for the trouble!

I couldn’t say, I’ve never used either. If it doesn’t do it already, it might be worth raising in the Smoldering Durtles thread. Or contact the WaniKani team to see if something in the back-end needs fixing.

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Try resetting the database in flaming durtles and see if that fixes it. You can do that under settings.

Sadly this didn’t work. :frowning: Thanks for trying, though…

Thanks! I’ll contact WK team to see if they can fix this!


Any word on whether this got fixed and how? I use Flaming Durtles but I find this a little unnerving.

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You should also switch to Smouldering Durtles, regardless of whether you’ve come across the same issue. Flaming Durtles isn’t supported any more, which means that as WaniKani starts to add more features, it’s only going to get more broken.

Just to give a different point of view, I don’t disagree with Belthazar’s advice, but I’m still using Flaming Durtles and not particularly worried that it can get broken or that WK can have the problem OP has.

I believe what’s happened, for the record, is that there are some words that have been added/changed/moved around to Wanikani that Flaming Durtles isn’t updated to. By doing those words when Flaming Durtles believed there were 0 Lessons (whereas my desktop app said 5), I think I accidentally made it so Flaming Durtles, communicating with WaniKani, counted my lessons/words as “-5” (negative 5), which might be causing the issues. The issues only exist on desktop and not when using Smouldering Durtles, so I’m going to continue using Smouldering until I rank up to Level 12 and then reset my progress to Level 12, hopefully cleaning everything out and ideally fixing the problem. If not, I’ll contact WaniKani and see what they can do.

I’m not sure what you mean by “WaniKani can’t have the problems I’m having” since, unless you think I’m lying, that… makes no sense. I’m having the problems, therefore Wanikani can have the problems.

Anyway, @AimForKoshien and @Belthazar I’ll keep you updated.

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It’s “[I’m] not particularly worried that … WK can have the problem OP has”. That is, not “the problem doesn’t exist” but rather “I don’t think it’ll happen to me”.

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It’s not the first time Wanikani adds or moves items, I’ve had the lesson count being different for a while for that reason, because the app only shows me items that are until the last level I’ve unlocked, while the website shows all the unlocked items. But I haven’t seen “NaN” and I don’t mind the numbers being different.

Flaming durtles will work fine, as long as you never do any of the kana only vocab lessons on the desktop. Once you introduce those into your lesson queue, you start running into undefined behaviour while using Flaming durtles.

I don’t really see though what an app like Flaming durtles could possibly do to make the desktop display NaN lessons. That almost has to be a coding mistake on wanikani’s side because:

  1. Flaming durtles can only interact with wanikani through the wanikani API.
  2. It should not be possible to break the lesson count by only sending valid API requests.
  3. It is the responsibility of wanikani to reject invalid API requests.

Also, “NaN” is generally the result of trying to calculate 0/0, or taking a square root of a negative number, and I’m not too clear on where division or square roots would show up when calculating numbers of lessons.

In my case I don’t have a NaN on Wanikani display but I do have differences in my count of items in different stages. For example, in Wanikani I have 4012 items burned but in FD I have 3997. Update: I moved to Smouldering Durtles and now it’s working :smile:

I never did them on desktop but they showed up as radical lessons. They’ve been working fine, only the label “radical” instead of “kana” is wrong

That is the thing with undefined behaviour, it might work fine, it might not work at all, or any number of options in between. There is no good way to predict what the result will be.


You’ll never guess when this issue started…