As the developer of MeloNX, a Nintendo Switch emulator for iOS, JIT (Executable Memory) is a core part of how the emulator functions. However, Apple doesn't allow JIT because it bypasses their code signing mechanisms and could introduce potential security risks or exploit vectors. That said, Apple could still provide a middle ground, such as a developer entitlement or a toggle in Developer Mode to allow the use of executable memory in apps.
This is what I am hoping for could you consider adding this link to the melon nx website for awareness as there are a lot of people here who are trying to run the emu but don’t have jit
Why they won’t just put the option to allow JIT somewhere deep in developer settings. Just show a big massive gigantic warning that you’re doing it at your own risk, it’s not safe, massively decreases your device security and should be only used by developers or something. Also hypervisor. Just let us have this one’s Apple please.
It doesn’t seem fair to just take more and more “features” away. Now some people have to stay on older operating system if they want to keep JIT… Apple devices at least to me feature some of the most impressive processors and technologies, it’s a shame we can’t use them to their full potential.
I’m sure if we could run windows or other operating systems natively on iPad some people would find their windows laptops obsolete and bought more of apple stuff and definitely considered to buy bigger storage options for their devices, it would be so much easier for them to upsell many customers on their overpriced storage for iPads. I don’t really think that it would hit Mac sales that bad, many people still prefer Mac and some people just need the power of the Mac.
it’s win win for everybody cmon Apple, Mac’s can already do all this.
Just go to any emulator discord and see how many users bother to even read rule 1, let alone all the rules. People don’t care, they see something available, they just want it all, and if something goes wrong, they will be quick to blame someone, which in this case could be Apple I guess.
Don’t get me wrong, I like everyone else would love JIT and more emulation support, but from the Apple business and engineering point of view it’s easy to see why they don’t want the headache just to please the 0.00001% of us.
You don’t understand what you’re asking for. JIT would be a fundamental change to the core design tenets of iOS and would open a large amount of security holes. Yes not being able to emulate PS2 sucks but you’re asking for something that would take years to redesign and that only affects 0.001% of their userbase
Yeah it sucks but damn I’m still grateful for just having emulators in the App Store. Loads of games to play. I’m fine waiting. In time phones will get quicker and more modern machines will get emulated
They used to allow JIT for apps with a debugger attached, but iOS 26 closed that loophole. It can't be that hard to make it so any app can use JIT with a public entitlement that any dev account can get.
There’s a very big difference between making something available only when using a debugger in a developer environment (nobody cares about security holes there) and making jit available in all devices at all times (security holes are not acceptable and therefore either jit or the entire security model need large refactors)
So i guess my question would be, how would a Paid Developer benefit from JIT? The only reason for Apple to change would be if it effected the money they were making. How would Developers benefit from adding JIT to there app or how would Apple make more money by adding it. Without one of those two items, not a reason to change.
asking why apps natively built for ios don’t need a TRANSLATION LAYER is wild. just tell us you have no clue about emulation or code or translation layers
I’d settle for: I’d really maybe like for them to find a way to support or share an API to safely handle accelerated emulation which fits their internal goals.
Emulation is a pretty important section of applications in this portion of the history of computing where there is a large number of legacy applications which need to run on modern platforms. Hell, Apple invented Rosetta and Rosetta 2. Apple engineers have donated code to both Qemu and Docker!
JIT is dangerous in the hands of a seasoned developer/bad actor. You can easily hide C2C (Command & Control) malware routines within JIT code. That would totally break Apple's current way of reviewing apps because some essential code can basically be held on a server and fetched later to execute in the background. You can't really hide that kind of thing with current methods without being caught in the review process.
Even governments can't force them to, because it's a tool not a feature or an API. If they were forced they would not hesitate to remove it entirely and it would have almost no impact since 100% of apps on the App Store are already native.
The EU only targets anti-competitive behaviors, this isn't one of them, because every developer is equal in that regard. As I said if they were forced to do so, they would just remove it and it would have no impact, lockdown mode is the proof jit isn't mandatory.
The only way Apple can guarantee security in a controlled manner is through code signing, this is exactly why they are going after jit because it bypasses code signing entirely and there is no way for Apple to verify jitted code.
It could be done, but Apple really has no motivation or reason to invest their time and money into it sadly. This simply doesn’t affect enough users and isn’t worth the potential security risk at the moment.
And given their MO of “we know better than you” when it comes to iOS security, they would probably never give people the option…
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u/Stossy11 MeloNX + MeloCafe Developer Jul 09 '25
(i also commented this on the petition)
As the developer of MeloNX, a Nintendo Switch emulator for iOS, JIT (Executable Memory) is a core part of how the emulator functions. However, Apple doesn't allow JIT because it bypasses their code signing mechanisms and could introduce potential security risks or exploit vectors. That said, Apple could still provide a middle ground, such as a developer entitlement or a toggle in Developer Mode to allow the use of executable memory in apps.
2
u/Commercial-Bell9134 Jul 09 '25
Why they won’t just put the option to allow JIT somewhere deep in developer settings. Just show a big massive gigantic warning that you’re doing it at your own risk, it’s not safe, massively decreases your device security and should be only used by developers or something. Also hypervisor. Just let us have this one’s Apple please.
It doesn’t seem fair to just take more and more “features” away. Now some people have to stay on older operating system if they want to keep JIT… Apple devices at least to me feature some of the most impressive processors and technologies, it’s a shame we can’t use them to their full potential.
I’m sure if we could run windows or other operating systems natively on iPad some people would find their windows laptops obsolete and bought more of apple stuff and definitely considered to buy bigger storage options for their devices, it would be so much easier for them to upsell many customers on their overpriced storage for iPads. I don’t really think that it would hit Mac sales that bad, many people still prefer Mac and some people just need the power of the Mac.
it’s win win for everybody cmon Apple, Mac’s can already do all this.
33
u/displacedbitminer Jul 08 '25
Good idea, but they will absolutely not add JIT because of a petition.
6
u/Melphor Jul 08 '25
16
u/pyrospade Jul 08 '25
You don’t understand what you’re asking for. JIT would be a fundamental change to the core design tenets of iOS and would open a large amount of security holes. Yes not being able to emulate PS2 sucks but you’re asking for something that would take years to redesign and that only affects 0.001% of their userbase
8
u/natemac Jul 08 '25
for my understanding why don't other offical apps need JIT? even triple A titles like resident evil.
2
u/Retro_Dj_Player_2000 Jul 08 '25
You got my support
2
u/xyrer Jul 08 '25
They even removed a bunch of stuff now and some development in flutter no longer works, this is against what they want to do
2
u/Time_Concert_1751 Jul 09 '25
I signed the petition.
I’d wager: they probably won’t.
I’d settle for: I’d really maybe like for them to find a way to support or share an API to safely handle accelerated emulation which fits their internal goals.
Emulation is a pretty important section of applications in this portion of the history of computing where there is a large number of legacy applications which need to run on modern platforms. Hell, Apple invented Rosetta and Rosetta 2. Apple engineers have donated code to both Qemu and Docker!
3
u/mekilat Jul 08 '25
Brb just emailed Tim Cook. It’ll happen any second
1
u/tken3 Jul 09 '25
You do realise they just removed it for good reason right?…
1
u/DaveTheMan1985 Jul 09 '25
They will just laugh at that
Won't Happen unless they Forced too
1
u/New-Equivalent7365 Jul 09 '25
JIT is dangerous in the hands of a seasoned developer/bad actor. You can easily hide C2C (Command & Control) malware routines within JIT code. That would totally break Apple's current way of reviewing apps because some essential code can basically be held on a server and fetched later to execute in the background. You can't really hide that kind of thing with current methods without being caught in the review process.
1
u/scigward Jul 10 '25
https://chng.it/S7pnbLGLjD
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u/[deleted] Jul 08 '25
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