Like being able to do quick cycles of fastboot boot out/arch/arm64/boot/Image.lz4-dtb , but annoyed by the lack of root this way? Well this atrocious idea might be the thing for you! It makes su always just work.

This is an awful idea! If you're silly, you'll add this to your kernel, and then forget to turn it off for production builds, and then very bad things will happen. This here probably is not for you! If you're reading this sentence, start backing away slowly! Out, damned spot!

From inside a clean kernel tree of yours:

$ curl -LsS "https://git.zx2c4.com/kernel-assisted-superuser/plain/fetch-and-patch.sh" | bash -

Then, make sure CONFIG_ASSISTED_SUPERUSER=y is enabled.

But don't do it! I take no responsibility for the dumpster fire this will cause. You'll probably forget to remove this for your release kernels. There are probably better ways to manage this kind of thing anyway. Don't do it! Just say "no" to backdoors! N.O.