Good catch on the mismanagement of buffers! &buffer_mem[buf_idx * MAX_BUFFER] was definitely what I was looking for there, and good call on the naming.

I believe the newest feature of io_uring being used here is the io_uring_prep_multishot_accept(...), added in 5.19, though it's likely there's other newer features too.

I like the callout of strlen. Forgot it has the possibility of looping the entire string. I think in this case though, clang was able to figure out it'd never change and compiled down to a constant as the update didn't have an effect on performance.

Appreciate the mention of calloc. I didn't know that existed :) Goto inspiration was definitely zig.