Staff Fullstack Software Engineer, Core Performance

As a Staff Software Engineer at Dropbox, you'll be the singular technical owner of application performance across the Core org — the part of Dropbox that owns every consumer-facing surface: web, iOS, Android, and desktop. This is one of the company's most visible, cross-cutting technical challenges. Your mandate is to make Dropbox feel fast on every surface our customers use. You'll operate at the intersection of measurement, engineering, and product impact, owning ambiguous problems that span the entire stack and translate directly into business outcomes for hundreds of millions of users.

There is no existing performance team at Dropbox — you'll define the discipline. You'll start with the web, profiling our highest-traffic React surfaces, producing flame graphs and heat maps, identifying the most valuable opportunities, and driving fixes through to shipped, measured wins. The web is your initial focus and the surface where you'll be most hands-on. From there, you'll lead the performance initiative across iOS, Android, and desktop by partnering with the internal platform experts who own those clients — coordinating strategy, transferring measurement practices, and driving the work, rather than building everything yourself. You'll also work across the Python and Go backend services that all of these surfaces depend on, since perceived performance rarely lives in one layer.