up - Node powered zero downtime reloads and load balancing

A pair of projects from LearnBoost are worth checking out. Distribute is load balancing middleware for Node. Up builds on top of Distribute to offer zero downtime reloads using either a JavaScript API or command line interface:

$ up --port 80 --watch some-http-server.js

This command spins up some worker processes (defaulting to how many CPUs on the box, or one in development environments) which serve up your requests. When a reload signal is received, Up spins up another set of workers and releases the old set after the the first worker of the new set is bound to a port. Eventually, all the new workers will join the round robin.

Check out Guillermo Rauch’s project announcement or the README for complete CLI usage and JavaScript API options.