Senior iOS Engineer - Brazil

Picture this: A white-labeled flagship mobile app with tens of millions of users, built to help healthcare organizations deliver smarter services with integrated fintech capabilities . Engineered to the highest security standards and trusted by over 300 enterprise clients , this is a platform at massive scale. We are completely rebuilding this entire ecosystem from scratch, meaning your work will directly shape how millions of people access and manage their health and finances using a 100% blank canvas. Do you want to be part of the team building something that impacts so many lives? We’re looking for an experienced iOS Engineer with deep expertise in Swift and SwiftUI to help us architect this next-generation mobile application from the ground up. In this hands-on role , you’ll leverage a highly modular, package-based approach to design clean, isolated, and scalable components tailored for our complex white-label requirements. If you enjoy solving deep architectural problems, setting foundational best practices without the burden of legacy code, and making a direct impact as a key technical contributor, this role is for you. Our Mission, Vision, and Values At Keystone AI , we prioritize alignment with our clients and team, ensuring a deep understanding of their needs. We are committed to delivering exceptional work while supporting the personal and professional growth of our team members. About Working at Keystone AI Our team is around 60+ people, primarily based in Croatia, but also members in South America, Serbia, and the US; the product team mostly being in the US, and engineering in Croatia and Brazil We are remote-first, but occasional travel may be required, e.g. for annual company retreats in Croatia We work on end-to-end projects with a long-term vision We strongly support work-life balance for our team members, even though we work in different time zones Requirements 5+ years of native iOS application development Strong expertise in Swift and modern iOS development practices (SwiftUI, Combine, UIKit, etc.) Working knowledge of backend APIs, authentication, and data persistence (REST/GraphQL, Core Data, Realm, …) Experience with iOS system architecture , performance optimization, and scalability Hands-on experience with app deployment and distribution via the App Store Comfortable with Git workflows, testing frameworks (XCTest, XCUITest), and CI/CD pipelines Strong written and spoken English skills This is a fully remote role for candidates based in Brazil. Bonus points if you have: Experience with large-scale consumer apps or high-impact user bases Knowledge of app security best practices, analytics, and observability tools Key Responsibilities Build and maintain high-quality native iOS apps using Swift and SwiftUI Develop clean, scalable UIs aligned with Apple’s Human Interface Guidelines Collaborate cross-functionally with Android development, product, design, and QA teams Contribute to architecture decisions, performance tuning, and scalability planning Integrate with backend APIs and ensure reliable data flow Stay current with iOS development trends and new iOS releases Take ownership of features and drive them from concept to deployment Qualities for Success Proactive, solutions-driven mindset Strong attention to detail and code quality Comfortable making technical decisions independently Passion for learning and improving Ownership mentality where you care about the end product Where You've Likely Developed These Skills Digital product agencies or consultancies, or in a product IT company Cross-functional product teams building real-world apps You're a great fit if you Love building polished and user friendly mobile apps Value quality delivery and ask the right "Why?" questions Want to grow technically while working on impactful projects Thrive in a collaborative, remote-first environment Like shipping clean, reliable code that solves real user problems This role is not a fit if you: Need constant oversight or micromanagement Are looking for a chaotic startup environment with unclear direction Benefits What's In It for You Real Impact: Real influence on technical decisions, tooling choices, and project direction. Compensations: $4.500,00 – $6.000/monthly for B2B engagement, based on experience and skills. Remote-first setup Health & Wellbeing: 100% paid sick leave + annual health checkup Stay active: Wellness subsidy Continuous Growth: An education budget specifically designed to fuel your learning and help you expand your knowledge base. Extra perks: Referral bonus Keystone AI is not responsible for any job boards scraping this ad without showing the position as remote, but Brazil exclusive. Applicants from other countries will not be considered. Keystone AI is committed to providing an environment of equal employment opportunity. We do not discriminate on the basis of race, color, religion, sex (including pregnancy, sexual orientation, or gender identity), national origin, age, disability, ge