Senior iOS Engineer, Growth Mobile

Block • San Francisco Bay Area, CA

15d

About The Position

Since we opened our doors in 2009, the world of commerce has evolved immensely, and so has Square. After enabling anyone to take payments and never miss a sale, we saw sellers stymied by disparate, outmoded products and tools that wouldn't work together. So we expanded into software and started building integrated, omnichannel solutions – to help sellers sell online, manage inventory, offer buy now, pay later functionality, book appointments, engage loyal buyers, and hire and pay staff. Across it all, we've embedded financial services tools at the point of sale, so merchants can access a business loan and manage their cash flow in one place. Afterpay furthers our goal to provide omnichannel tools that unlock meaningful value and growth, enabling sellers to capture the next generation shopper, increase order sizes, and compete at a larger scale. Today, we are a partner to sellers of all sizes – large, enterprise-scale businesses with complex operations, sellers just starting, as well as merchants who began selling with Square and have grown larger over time. As our sellers grow, so do our solutions. There is a massive opportunity in front of us. We're building a significant, meaningful, and lasting business, and we are helping sellers worldwide do the same. The Role The Growth Mobile team is the only mobile-focused team within Square's Growth organization, on a mission to create seamless, data-driven mobile experiences that empower sellers to grow and succeed. We operate under SOAR principles: Sustainability (leave code better than you found it), Observability (build with insight by default), Agility (rapid experimentation), and Reliability (build with confidence). Our team owns three critical domains: Growth (driving acquisition, activation and adoption), Identity (secure authentication and payment activation), and Monetization (subscriptions and upsells). We own critical features and seller flows across Square's mobile ecosystem, including: Authentication & Identity: Login, account creation, secure authentication flows Seller Onboarding: Modes recommendation flow, setup guide, getting started experiences Payment Activation: Payment onboarding, Know Your Customer verification, bank account setup Hardware: Hardware ordering and fulfillment flows Referrals: Growth and viral mechanics Monetization: Subscription gating, subscription management, upsells, pricing flows This is a high-impact role where you'll own mission-critical systems that every Square seller interacts with.

Requirements

• 7+ years of iOS development experience with deep expertise in Swift and Objective-C.
• Proven experience in architecting and leading complex iOS projects at scale.
• Strong collaboration skills, with experience working across teams and functions to deliver cohesive, user-focused solutions.
• Experience mentoring engineers and leading by influence.

Responsibilities

• Architect and improve iOS systems for authentication, onboarding flows, payment activation, hardware ordering, referrals, and subscription management
• Build server-driven experiences enabling rapid experimentation without traditional release constraints
• Lead A/B testing initiatives to optimize activation funnels and drive quarterly conversion improvements
• Partner with Android engineers, PMs, designers, and data scientists to deliver data-driven features with platform parity
• Implement comprehensive monitoring and observability for critical flows with real-time dashboards
• Systematically reduce technical debt while expanding server-driven coverage for same-day deployments
• Mentor engineers and establish best practices collaboratively.
• Support on-call rotation and contribute to cross-platform frameworks like FormContainer

What This Job Offers

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