Small static file (174 B) - the bread and butter of static sites:
server req/s p99
zeroserve 36,681 5.4 ms
nginx 31,226 7.8 ms
Caddy 12,830 22 ms
zeroserve serves small files about 17% faster than nginx on a single core, with a tighter tail. HTML pages, small JSON, CSS - this is the case zeroserve is tuned for.
Large static file (100 KB):
server req/s throughput p99
zeroserve 8,000 782 MB/s 22 ms
nginx 7,600 773 MB/s 28 ms
Caddy 6,084 590 MB/s 44 ms
I'd go with a more storied project that's been audited, battle tested, hardened etc than this upstart. There's not enough improvement to justify the risk.
I could totally see "Small static files are the bread and butter of static sites" appearing in some pointless deck on a Zoom call.