Senior iOS Engineer, Contractor (Brazil)

**Primary Responsibilities** * Design, build, and maintain customer\-facing iOS applications with a focus on quality and performance * Collaborate with Product and Design teams to define, design, and deliver new features * Take ownership of the iOS codebase architecture, ensuring scalability, reliability, and maintainability * Partner with backend and firmware engineers to design end\-to\-end solutions * Mentor junior engineers through code reviews, pair programming, and technical guidance * Advocate for coding standards, testability, and performance best practices within the team * Identify and resolve complex technical issues, including debugging and performance optimization * Stay current with iOS ecosystem trends and proactively recommend improvements * Participate in Agile ceremonies, contributing to sprint planning, estimation, and retrospectives * Maintain clear technical documentation for features, architecture decisions, and best practices **Requirements** * 5\+ years of iOS app development experience, with a portfolio of shipped apps * Expertise in Swift and SwiftUI, with deep knowledge of iOS SDK frameworks and Apple's design guidelines * Strong computer science fundamentals: data structures, algorithms, concurrency, memory management * Proficient in REST APIs, JSON data handling, and integrating third\-party SDKs * Experience with unit/UI testing, CI/CD pipelines, and Agile development practices * Skilled in debugging, profiling, and optimizing mobile applications * Strong problem\-solving and communication skills, able to work effectively in cross\-functional teams * Ability to rapidly prototype and iterate toward production\-ready features **Bonus Skills** * Experience with iOS Bluetooth Low Energy (BLE) APIs * Familiarity with cross\-platform libraries * Experience working with Google Firebase APIs