Interesting... I've been playing with the idea of embedding more python in my C, no cython or anything just using <Python.h> and <numpy/arrayobject.h>. From one perspective it's just "free" C-bindings to a lot of optimized packages. Trying some different C-libraries, the python code is often faster. Python almost becomes C's package manager

E.g. sorting 2^23 random 64-bit integers: qsort: 850ms, custom radix sort: 250ms, ksort.h: 582ms, np.sort: 107ms (including PyArray_SimpleNewFromData, PyArray_Sort). Where numpy uses intel's x86-simd-sort I believe.

E.g. inserting 8M entries into a hash table (random 64-bit keys and values): MSI-style hash table: ~100ns avg insert/lookup, cc_map: ~95ns avg insert/lookup, Python.h: 91ns insert, 60ns lookup

I'm curious if OPs tool might fit in similarly. I've found lmdb to be quite slow even in tmpfs with no sync, etc.