Roarr
JSON logger for Node.js and browser
...For example, a transport might send the log line to a standard syslog server after processing the log line and reformatting it. Roarr does not support in-process transports because Node processes are single threaded processes (ignoring some technical details). Given this restriction, Roarr purposefully offloads handling of the logs to external processes so that the threading capabilities of the OS can be used (or other CPUs).