Kamailio is an open source SIP routing server known for its robustness, solid security and high performance. This talk shows how Kamailio can leverage Lua scripting language to extend its capabilities as well as bring its flexibility to the next level. From reloading Lua routing rules without restart, to importing Lua native libraries, Kamailio becomes the SIP routing engine that can facilitate building from classic telephony systems to modern real time communication platforms.