Sean Cook, who announced last week he was leaving Twitter after five years, is planning to join messaging startup Layer as head of product, Re/code has learned.
Cook, who held a variety of mobile roles at Twitter, was most recently product manager for Fabric. During his time at Twitter he also led mobile partner integrations, mobile device partnerships and mobile engineering.
“After years of working on mobile integrations, I’ve come to realize that there are rudimentary building blocks that all apps need,” Cook told Re/code. “Layer not only provides one of these building blocks, it does so with a strong focus on another one of my passions: Delighting developers.”
Cook says Layer is trying to build an open communications layer that allows app makers to easily make communications a native part of their creations.
Other notable Layer hires include former Apple engineer Andrew Vyrros, who worked on iMessage and FaceTime. (Update: Vyrros actually no longer works at Layer, having left last year after just three months at the company.)
This article originally appeared on Recode.net.