Senior iOS Engineer

Phia • New York, NY

15d

About The Position

As a Senior iOS Engineer focused on the Homefeed at Phia, you’ll build the core mobile experiences users interact with every day. You’ll work on high-traffic, performance-critical surfaces that drive discovery, engagement, and retention. This role sits at the intersection of mobile engineering, product iteration, and platform capabilities, with ownership over features that shape the heart of the product. You’ll ship frequently, optimize for speed and reliability, and help define how the iOS app scales as the audience grows.
About Phia
Phia has raised $43M from Notable Capital, Khosla Ventures, and Kleiner Perkins to build the AI alignment layer for commerce. In under a year, Phia’s consumer shopping agent has surpassed one million users and partnered with 6,200+ retail brands, representing billions in annual gross merchandise volume. Each month, Phia drives millions of dollars in sales for brands and has achieved 11× revenue growth since launch.
In an era where AI vertical agents are reshaping every industry, commerce is on the verge of a complete transformation. Phia is reinventing shopping from a fragmented, impersonal experience into one that feels intelligent, trusted, and built around each user’s intent. This foundation of trust is our wedge to become the end-to-end shopping destination for the next generation of buyers.
Phia is a lean, high-ownership team building at startup speed. If you want to ship at high velocity and solve complex problems in consumer AI and commerce, this is the place to do it.

Requirements

• 5+ years of experience building and shipping iOS applications in production
• Strong proficiency in Swift and deep experience with SwiftUI
• Proven experience building feed-based or content-heavy mobile surfaces
• Strong understanding of performance optimization, memory management, and rendering pipelines
• Experience collaborating with product, design, and backend teams
• Ability to own complex features from concept through launch and iteration

Responsibilities

• Own the iOS home feed experience end-to-end, from architecture to UI polish
• Build high-performance, scroll-heavy feed UIs optimized for smoothness, responsiveness, and memory efficiency
• Partner with ML and backend teams to integrate ranking and personalization systems into real-time product experiences
• Collaborate with Product and Design to iterate quickly through A/B testing and experimentation
• Lead technical decisions around state management, feed architecture, and rendering performance
• Identify and resolve performance bottlenecks, crashes, and edge cases
• Set best practices for iOS feed development, mentoring other mobile engineers
• Participate in design reviews, code reviews, and technical planning

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Education Level: No Education Listed