Sam BurkhardWrote a markdown parser in C recently just for fun! Here's it benchmarked against pandoc with a small file:
And here it is against a larger file (only 26 MB bc pandoc freaks out on huge files). For reference, pandoc used >3.5GB of RAM for this. 69.27s vs 0.47s!
Repo: https://github.com/srburk/MarkCore. It's built as a static lib by default since I made it to embed into another project where I wanted to control dependencies.
I used Address Sanitizer a lot during development which was great, and started using LLDB more after finding a cheat sheet for GDB->LLDB commands.