What quality open source projects are there on github (or elsewhere) to explore?

Question

linux

Good afternoon!
I am looking for open source projects to learn from, write good code (meeting all the requirements of quality code, such as clarity, completeness, conciseness, portability, consistency, maintainability, scalability, testability, reliability, etc.). If anyone has experienced anything similar, please share.
Interested primarily in c++/c projects. If system, then under Linux.
Thanks everyone :)

Answer 1

Here somewhere it was recommended to start with standard Linux tools. Take the source code of the same grep and have a look. Verified over the years, in theory.
But do not think that OpenSource de facto meets the "requirements for quality code."