Library/Proxy yours Don’t do this Of course It’s perfect I got it Easy Obviously, it’s Go OS nginx YES 3rd party (ngx-lua). Not complete (no TCP support). Possible for HTTP via ngx-lua. No TCP yet Sidekick for new upstreams. Manipulate existing via ngx-lua No, try via sidekick/ ngx-lua Landed in 1.9.0, stabilized in nginx+ Proxy haproxy YES Lua support in master Not scriptable, only rate limiting built-in Sidekick and reloads (with iptables wizardry), manipulate existing admin socket No, try via sidekick Built as L4 Proxy vulcand Maybe? middlewares, requires forking SOME, only circuit breaker Beautiful HTTP API etcd support No, only supports HTTP currently (not in ROADMAP.md) Proxy finagle YES YES, completely centered around plugins YES, sophisticated FailFast module YES Zookeeper support Application-level Library, requires JVM smartstack Somewhat However much HAProxy is, adapters NO, same as HAProxy YES Zookeeper support Yes, uses HAProxy Proxy + discovery