Staff Fullstack Software Engineer, Core Performance

Dropbox is seeking a Staff Software Engineer to own application performance across its Core organization, which includes all consumer-facing surfaces. The role involves driving performance improvements, defining measurement standards, and leading initiatives across web, iOS, Android, and desktop platforms.

Responsibilities:

• Drive performance improvement on the Dropbox web application as the first focus of the role — profiling React surfaces, producing flame graphs and heat maps, identifying the highest-impact opportunities, and shipping measurable improvements
• Lead the performance initiative across iOS, Android, and desktop by coordinating with internal platform experts who own those clients — setting strategy, defining measurement standards, and driving execution rather than implementing every fix personally
• Take performance improvements end-to-end: from measurement, to root-cause analysis, to shipped code changes, to validation in production telemetry
• Build and own the measurement, instrumentation, and regression-detection systems that engineering teams across Core depend on to ship performant code
• Write production code regularly — primarily JavaScript and React on the web, with backend work in Python and Go on the services those surfaces depend on
• Set engineering standards for performance work across Core Engineering, and mentor IC3 and IC4 engineers on profiling, measurement methodology, and performance-aware system design
• Apply AI tooling to performance work and lead the optimization of AI-assisted engineering workflows across Core, raising engineering throughput and shaping how Dropbox engineers use AI to ship better software faster
• Influence cross-org roadmaps and architectural decisions, partnering with engineering leaders, PMs, and designers to ensure performance is treated as a first-class product attribute

Requirements:

• BS, MS, or PhD in Computer Science or a related technical field involving coding (e.g., physics or mathematics) or equivalent technical experience
• Minimum of 12 years of experience as a software engineer with 3+ years serving as a Senior
• Demonstrated, hands-on experience driving measurable performance improvements in production web applications — including profiling JavaScript and React surfaces, identifying root causes through flame graphs, heat maps, traces, and RUM data, and shipping the fixes that moved the metric
• Demonstrated experience using AI tooling to accelerate performance work — applying LLMs and AI-assisted workflows to profiling analysis, root-cause investigation, refactoring, or shipping performance fixes
• Experience optimizing AI-assisted engineering workflows to improve the productivity of other engineers — selecting tools, defining patterns and guardrails, and measuring the impact on engineering throughput
• Production experience with modern backend services in Python or Go that support consumer-facing client surfaces
• Experience leading technical strategy on cross-cutting initiatives spanning multiple teams or surfaces, including writing design docs, defining architecture, and driving execution to measurable outcomes
• Has worked on a consumer user-facing product (versus a platform team or developer-facing API-based product), and shipped changes that moved customer-visible metrics
• Strong written and verbal communication skills, with a track record of influencing roadmaps and decisions outside their direct reporting line — including leading initiatives that depend on coordinating with platform owners they don't directly manage
• Experience profiling and improving native iOS applications (Swift), including startup time, scroll performance, and memory behavior
• Experience profiling and improving native Android applications (Kotlin), including startup time, scroll performance, and memory behavior
• Experience profiling and improving desktop client applications, including startup, IPC, and resource usage
• Experience building or owning performance regression-detection systems integrated into CI/CD
• Experience with RUM telemetry pipelines, sampling strategy, and statistically rigorous comparison of performance data
• Track record of mentoring senior engineers (Senior and above) and raising the technical bar across an engineering organization