Would it be possible to make a fangame a .nds data so that you can play it on a flashcard or something on your DS?

This has been debated (privately) with KSA for a while, but is unlikely to happen soon, or maybe even at all.

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Edit: ah Luke beat me to it.

I was actually thinking of an .nds version of the pywright engine, but it is a long shot and wont be happening for a while. The PyWright core as it stands is far too complex at the moment to think of porting, but there are some key areas where simplifications can happen. I wouldn't give a date because chances are high that I will give up the idea before I am able to. So don't expect it at all in any case. Programming for ds is pretty difficult, even for simple applications.

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In my case, I would need to reimplement AIGE to the DS (excluding all unnecessary things). The current AIGE would need heavy modification to make AHLSL run in two different processors (the ARM7 and ARM9 from original DS), so a full new version of it would be needed.
I might one day work on it, but not sure. AIGE is more complex then PyWright (since AIGE runs PWLib that is on AHLSL while PyWright is directly a pw engine), so I won't be able to do it anytime soon. Also there are lots of work to do with AIGE, and I won't divert to make it on DS (it is time consuming).

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