fopro

An proof-of-concept(TM) caching HTTP forward proxy

Limitations

Very naive rules to decide if something is cachable (see sources) specifically, fopro DOES NOT RESPECT cache-control, vary, ETC.
The cache is boundless (both in memory and on disk)
Responses are buffered in memory completely before being proxied (instead of being streamed)
Partial responses (HTTP 206) are not cached at all.
Really you shouldn't use fopro, it currently does the bare minimum to get most of the uv test suite passing.