Staff iOS Software Engineer, Product Platform

Block builds technology and financial products through brands including Cash App and Square. The Staff iOS Software Engineer will provide hands-on, organization-level technical leadership for Product Platform by building foundational iOS systems, shared frameworks, developer tools, and AI-assisted development capabilities. The role will drive architecture, migrations, reliability, security, performance, developer experience, and cross-team technical standards.

Responsibilities:

• Own and evolve foundational iOS systems, such as application architecture, navigation, deep linking, dependency management, lifecycle management, and shared user interface foundations
• Design shared libraries, frameworks, and developer tools that product teams rely on
• Find and frame systemic iOS problems that do not yet have clear ownership
• Define technical strategy, architecture, standards, and measures of success across teams and applications
• Build prototypes, reference implementations, and critical paths that prove a direction before broader adoption
• Lead multi-quarter migrations and foundational initiatives from proposal through adoption
• Establish durable practices for testing, observability, performance, release safety, security, and maintainability
• Improve developer and AI ergonomics so both engineers and coding agents can work effectively with the platform
• Contribute platform technology to open source when it creates value for the broader engineering community
• Integrate AI-assisted development tools into daily workflows to drive leverage across product and platform engineering
• Evaluate emerging tools and practices, building durable, AI-powered platform capabilities where they add clear value
• Verify AI-assisted outputs and ensure high standards for software quality, security, and reliability
• Operate beyond your immediate team to identify and address cross-cutting technical problems
• Lead architecture and design reviews across team boundaries
• Surface systemic risks before they become customer, seller, or engineering problems
• Develop senior engineers and create ownership models that distribute expertise
• Help set technical standards that improve the quality and velocity of iOS development over time
• Partner with engineers, product managers, designers, and engineering leaders to align platform investments with product needs
• Work with Android, web, and backend engineers to improve shared product foundations and cross-platform experiences
• Represent iOS platform needs in cross-team and company-wide technical discussions
• Communicate complex technical decisions clearly to technical and nontechnical audiences

Requirements:

• 12+ years of professional software engineering experience
• 8+ years in roles where mobile engineering was a primary responsibility, including 4+ years building native iOS products
• Deep expertise across modern and legacy iOS frameworks, Swift, and Objective-C
• Experience creating foundational systems, shared frameworks, or developer tooling used across multiple teams
• A record of leading strategic, multi-quarter initiatives with broad adoption and durable impact
• Experience connecting platform strategy to customer-facing and multi-tenant SaaS products that support business operations
• Strong systems thinking, technical communication, mentoring, and organizational influence
• A platform builder's mindset. You treat engineers as customers and measure success through adoption and product outcomes
• Experience with large, modular iOS applications maintained by many teams
• Experience with build systems, continuous integration and delivery, testing infrastructure, observability, or mobile performance
• Experience supporting customer-facing or seller-facing products in financial services, commerce, or another high-trust environment
• Experience with experimentation infrastructure, feature flags, or large-scale product delivery
• Experience creating developer platforms that support both human engineers and AI coding agents
• A record of identifying and leading work that was not already on a team's roadmap