Blink shell: https://blink.sh/
code-server: https://github.com/cdr/code-server
For testing big builds or anything you want some power for, a good way to go when you need portability.
Technically you can compile iOS stuff on Linux or jailbreaked iOS, all you need is clang and apple toolchain. Examples: https://github.com/theos/theos/wiki or https://github.com/tpoechtrager/cctools-port/