Implementations of a routing tier for highly-available applications on a multi-tenant Platform-as-a-Service (PaaS) system are disclosed. A method of the disclosure includes receiving, from a broker of a multi-tenant PaaS system, information related to a load balancer gear of an application running on the multi-tenant PaaS system. The information includes endpoint information indicating a location of the load balancer gear, and cartridge information identifying one or more cartridges implemented on the load balancer gear. The method further includes updating a routing table in view of the endpoint information and the cartridge information, and causing traffic to be routed to the load balancer gear in view of the updated routing table. The load balancer gear directs traffic to one or more other gears of the application.