bleachisback
Re:How I cut GTA Online loading times by 70%
on Tuesday March 02, 2021 @12:47AM (#26312256)
The first C++ JSON library that appears when you google it is a single header file.
https://github.com/nlohmann/json
I know because I used it years ago in school.
One of the fastest libraries (https://github.com/miloyip/nativejson-benchmark#parsing-time) is also header-only and compares its speed to strlen.