How difficult is it to write a custom Android 5.1+ ROM?

[Ottonomous]

Due to the lack of any alternative ROMS for the Huawei mate 7/8 I was considering taking their recently released source code and adding the conventional tweaks modern cROMs provide (and to compete with KangROM's marshmallow beta).

I have minimal programming experience but I believe this wouldn't be a heavy undertaking for someone of beginner status.

Would the lack of support for HiSilicon's proprietary processors pose a problem? (Exynos procs were notoriously harder to crack than Snaps for instance).

How much time and effort investment would I be looking at, for instance, to achieve something within the level of CM13?

 

[teller]

In my opinion this is not task for beginner.

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[purbeast0]

Due to the lack of any alternative ROMS for the Huawei mate 7/8 I was considering taking their recently released source code and adding the conventional tweaks modern cROMs provide (and to compete with KangROM's marshmallow beta).

I have minimal programming experience but I believe this wouldn't be a heavy undertaking for someone of beginner status.

Would the lack of support for HiSilicon's proprietary processors pose a problem? (Exynos procs were notoriously harder to crack than Snaps for instance).

How much time and effort investment would I be looking at, for instance, to achieve something within the level of CM13?

while i've never written one, i have no clue how you came to the bolded conclusion with the programming experience you state you have.

 

[AMDisTheBEST]

You should work under guidance with an experienced coder. There are many Android open sourced projects out there. Call one of their developer and offer to contribute