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At T-Mobile, we invest in YOU! Our Total Rewards Package ensures that employees get the same big love we give our customers. All team members receive a competitive base salary and compensation package - this is Total Rewards. Employees enjoy multiple wealth-building opportunities through our annual stock grant, employee stock purchase plan, 401(k), and access to free, year-round money coaches. That’s how we’re UNSTOPPABLE for our employees! Job Overview We are seeking a highly skilled and motivated iOS Sr. Software Engineer to join the team powering the T-Life app—T-Mobile's flagship mobile experience. In this role, you will contribute to the design, development, and delivery of high-quality, performant, and AI-enabled iOS features that reach millions of users. The Sr. Software Engineer is essential for designing, implementing, and deploying scalable mobile software solutions that meet customer requirements and support high-availability environments. This role focuses on iOS application development within established architecture, collaborating with cross-functional engineering teams to build modern, reliable features and integrate backend services—including AI-powered capabilities. Success is measured by the ability to deliver dependable technical solutions, produce clear documentation, and contribute to continuous improvement and innovation that enhances customer experience and supports business goals.
Job Responsibility
Develop software solutions and conduct tests to drive engineering projects and ensure quality deliverables, including design and development of scalable iOS features using Swift and modern Apple frameworks
Contribute to design innovations that improve systems, processes, or services using new frameworks, architectural patterns such as MVVM or Coordinator, and industry best practices
Collaborate with technical teams to deliver solutions and mentor others through knowledge sharing and training sessions, including guidance on mobile engineering standards and AI-enabled feature integration
Support technology strategy by evaluating and applying current iOS technologies and mobile development trends that align with business goals
Create clear documentation for software code, system designs, and business requirements to support knowledge sharing and cross-team collaboration
Lead medium-to-large iOS initiatives, contribute to architectural decisions, and promote scalable, secure, and maintainable mobile application design
Integrate RESTful APIs and backend services, including AI-powered services that enable personalization, conversational experiences, recommendations, and intelligent automation
Ensure quality through strong unit testing, performance optimization, CI/CD participation, and adherence to security and App Store compliance standards
Mentor and coach junior engineers while providing technical leadership across cross-functional teams, promoting knowledge sharing, engineering best practices, operational excellence, and a culture of accountability and continuous improvement
Drive execution of daily operational activities, incident remediation, and service improvement initiatives, ensuring projects and operational commitments are successfully delivered through implementation, stabilization, and ongoing support
Also responsible for other duties/projects as assigned by business management as needed
Requirements
Bachelor's Degree plus 5 years of related work experience
OR advanced degree with 3 years of related experience
Acceptable areas of study include Computer Science, Software Engineering, Information Management, or equivalent experience in field
4–7 years of technical engineering experience
Proficiency in Swift and familiarity with Objective-C for legacy code maintenance
Experience with UIKit and/or SwiftUI for building production-grade iOS interfaces
Strong understanding of iOS app lifecycle, memory management (ARC), and performance optimization
Familiarity with dependency management tools (Swift Package Manager, CocoaPods)
Experience working with Git-based workflows and collaborative code review processes
Foundational exposure to AI-enabled backend services
Communication (Required)
Customer Service (Required)
Analytics (Required)
Technical Writing (Required)
At least 18 years of age
Legally authorized to work in the United States
Nice to have
Experience with SwiftUI for building modern, declarative iOS interfaces
Proficiency with Swift Concurrency (async/await) and/or Combine for reactive and asynchronous programming
Experience with architectural patterns such as MVVM, MVC, or Coordinator
Experience integrating RESTful APIs and backend services that support personalization or intelligent user journeys
Exposure to AI-powered APIs, LLM-backed services, inference endpoints, or recommendation systems
Familiarity with AI-assisted development tools (e.g., GitHub Copilot, ChatGPT Enterprise, Claude) to accelerate coding, documentation, and code review workflows
Knowledge of iOS accessibility standards and implementation (e.g., VoiceOver, Dynamic Type)
Experience with CI/CD tools for iOS (e.g., Fastlane, Xcode Cloud, TestFlight)
Familiarity with performance profiling tools (e.g., Instruments, MetricKit)
Experience working in Agile/Scrum development environments