Principal Engineer, Ios Performance

Reddit Reddit · Consumer · United States · Remote · Growth

Principal Engineer for Reddit's iOS Platform team, focusing on architecting the iOS app for massive scale (100M+ DAUs), improving modularity, performance, and quality. Responsibilities include defining and measuring performance goals (ANR rate, launch time, frame drops), enhancing observability, driving a performance culture, and mentoring engineers. Requires deep experience in large-scale mobile app development and influencing engineering organizations.

What you'd actually do

  1. 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.”
  2. Identify the gaps in our current iOS App Architecture, and lead redesign of the iOS platform to improve modularity, performance, and quality.
  3. 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.
  4. 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.
  5. 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.

Skills

Required

  • Deep experience-based understanding of how to build mobile applications at scale
  • Strategic thinker who thrives on developing a long-term technical foundation
  • Developing scalable, well-designed software
  • 10+ years of Software development experience
  • 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 Swift UI and structured Concurrency
  • Experience working with cross-functional teams such as design, product, data teams to deliver great user experiences

Nice to have

  • Passion for developing scalable, well-designed software that improves people’s lives globally

What the JD emphasized

  • scale for the next 100M+ DAUs
  • performance
  • App Not Responding (ANR) rate
  • app launch time
  • slow/dropped frames
  • observability
  • performance
  • performance