shadowsocks-libev (libev port of shadowsocks, a secure socks5 proxy)

Shadowsocks-libev is a lightweight secured SOCKS5 proxy for embedded
devices and low-end boxes. It is a port of Shadowsocks.
Shadowsocks-libev is written in pure C and depends on libev. It's
designed to be a lightweight implementation of shadowsocks protocol,
in order to keep the resource usage as low as possible.

You can get detailed information from official wiki:
https://github.com/shadowsocks/shadowsocks/wiki