Scalæ By the Bay

Finagle is an open-source, high-volume RPC client library which powers the application infrastructure of companies like Twitter, Pinterest and Soundcloud. In this talk, we introduce "linkerd", an open source RPC proxy built on Finagle and specifically designed for microservices. We describe how linkerd can be used to “wrap” polyglot multi-service applications in Finagle’s operational model, adding connection pooling, load balancing, failure detection, and failover mechanisms to existing applications with little to no code change. We demonstrate how this model allows polyglot applications to take advantage Finagle’s production-tested capabilities around scalability, reliability, and fault-tolerance, even in the presence of unpredictable traffic volumes and unreliable hardware. We describe how Finagle was used and extended in the creation of linkerd, and walk through the roadmap of upcoming features.