I did this as a start project of learning deeper how systems programming works, since it is something that really gets my attention. With this project I could understand how UTF-8's treatment are ...

I tried to closely follow the algorithms in the spec, as a way of testing them, but when it came to: "6. Increase utf-8 bytes seen by one and set utf-8 code point to utf-8 code point + (byte − 0x80) ...