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RedditRedditSan Francisco, CA

Principal Engineer, iOS Performance

Leads architecture and performance optimization of Reddit's iOS app to scale for 100M+ DAUs, defines standards and best practices, improves observability, and mentors iOS engineers company-wide. Requires 10+ years experience with 5+ in iOS and expertise in modern frameworks like SwiftUI.

233k – 326k
On-site10+ YOEiOS Engineering

About the role

Responsibilities

  • Own the architecture of Reddit’s iOS Mobile App and make it scale to the next 100M+ DAUs. Propose ideas/solutions to reach our vision of “making Reddit’s Mobile Apps best-in-class.”
  • Identify the gaps in our current iOS App Architecture, and lead redesign of the iOS platform to improve modularity, performance, and quality.
  • Define, measure, and execute on key user-facing performance goals, specifically minimizing App Not Responding (ANR) rate, reducing app launch time (Time to Interactive/TTFF), and eliminating slow/dropped frames.
  • Improve observability and harden data quality for all key performance areas, including establishing reliable telemetry, monitoring, and guardrails for ANR rate, app launch time, and slow/dropped frames.
  • Drive a company-wide culture of performance, ensuring that every iOS engineer at Reddit has the tools and skills needed to own the performance of their product surfaces.
  • Mentor iOS developers across the company.
  • Be the go-to person for developers on complex problems in iOS development.

Requirements

  • Deep experience-based understanding of how to build mobile applications at scale.
  • Strategic thinker who thrives on developing a long-term technical foundation and has a passion for developing scalable, well-designed software.
  • 10+ years of Software development experience with at least 5+ years in designing/developing iOS applications.
  • Experience in influencing larger (200+ engineers) organizations on technical direction/best practices related to iOS.
  • Experience with modern iOS development frameworks such as SwiftUI and structured Concurrency.
  • Passion for developing scalable, well-designed software that improves people’s lives globally.
  • Experience working with cross-functional teams such as design, product, data teams to deliver great user experiences.
  • Bachelor's degree or higher in Computer Science or a related field, or equivalent technical expertise.

Skills

iOSSwiftUIStructured ConcurrencyPerformance OptimizationApp ArchitectureTelemetryMonitoringSwiftMobile DevelopmentNetworkingCaching

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