write-byte unbuffered responses are slower than necessary
In the examples, /pic-gen loops reading a byte from a file and writing a byte to the response stream. The result is a chunked response that has one byte chunks. If the code is modified to use a 1000-byte buffer and write-sequence, it goes from 4 seconds to 0.1 seconds for a response.
Look into buffering write-byte to avoid this inefficiency.