Staff Fullstack Software Engineer, Core Performance

About the role

The Staff Fullstack Software Engineer, Core Performance role is a company‑defining position responsible for elevating application performance across every consumer‑facing surface at Dropbox: web, iOS, Android, and desktop. This is a foundational opportunity because there is no existing performance team; you will define the discipline from the ground up and establish how Dropbox measures, prioritizes, and delivers performance improvements at scale. The role operates at the intersection of measurement, engineering, and product, turning ambiguous, cross‑stack challenges into measurable business outcomes for hundreds of millions of users. Your work will begin with the web - the primary surface for this role - and expand systematically to other clients and backend services, embedding performance thinking into the core of Dropbox's engineering culture.

What you'll do

You will profile the highest‑traffic React experiences on the web, producing flame graphs and heat maps to pinpoint bottlenecks and highest‑value optimization opportunities. You will own the end‑to‑end performance of each user journey, driving improvements from code change through rollout and validation of real‑world impact. This includes shipping targeted experiments and coordinating their rollout, while establishing observability, tracing, and measurement foundations that clarify behavior under load across web modules. You will also review regression signals and alerting setups to ensure teams receive timely insight before quality degrades broadly.

From the initial web focus, you will extend the performance initiative to iOS, Android, and desktop, partnering closely with internal platform experts. In these collaborations, you will set strategy, transfer measurement practices, and drive execution so that performance practices spread consistently without you personally implementing every client fix. Performance is not limited to the client; you will also work with Python and Go backend services that Core surfaces depend on, because perceived latency rarely lives in a single layer.

Your influence will extend across Core Engineering as you define measurement standards, regression‑detection systems, and performance practices that other teams rely on. You will use AI tools in your own engineering work and lead the optimization of AI‑assisted workflows across Core, raising productivity for every engineer. By bringing clarity to ambiguous problems and raising the bar for engineering excellence through hands‑on leadership, you will shape how Dropbox thinks about performance for years to come. This role provides meaningful exposure to senior leadership, the chance to build foundational systems that unlock future product capabilities, and a path to grow into an org‑level technical strategist advancing Dropbox's mission.

Requirements

To succeed in this role, you thrive in ambiguous, cross‑functional contexts and translate broad problems into concrete, measurable work. You are comfortable profiling complex web stacks, analyzing performance data, and prioritizing based on user impact. You have experience coordinating with platform teams and influencing without direct authority, and you use AI tools to augment your engineering work while eager to set standards that raise the performance maturity of the entire organization. You understand the full stack enough to partner effectively with backend engineers on Python and Go services, and you can communicate clearly with mobile and desktop platform teams to align metrics and tactics. This is a hands‑on leadership role that demands both deep technical execution and the ability to define and own performance disciplines at scale.

Practical notes

You will work with modern web technologies, focusing on React experiences where you will create flame graphs and heat maps to identify and prioritize bottlenecks. You will build measurement foundations, including observability and tracing, to clarify behavior under load across web modules and surface actionable insights. You will review regression detection and alerting setups to ensure timely insight and prevent broad quality degradation. You will ship experiments and validate improvements, coordinating rollouts and confirming real user impact. You will partner with platform teams for iOS, Android, and desktop to align metrics and spread performance practices consistently. You will collaborate with backend engineers working in Python and Go to address cross‑layer latency and ensure end‑to‑end performance. You will define standards that raise the performance maturity of the organization and use AI tools to both augment your own work and optimize AI‑assisted workflows. You will exercise hands‑on leadership to resolve ambiguous, cross‑functional problems and elevate Dropbox's engineering excellence.

About the company

Dropbox is a file hosting service that offers cloud storage, file synchronization, and personal cloud software. Founded in 2007 by Drew Houston and Arash Ferdowsi, Dropbox has over 700 million registered users.