C++ Project Ideas ( :TODO:)

Hi all, I got a idea!
if you have open source project ideas please share them on this thread.

There are many tons of open source projects out there in the internet.
what here expected is fresher level complex code-bases.

:TODO: requests are welcome.

so the final year students who needed a project can have a idea what kind of
requirements/:TODO: are needed in the opensource world.

--Thanks in Advance--