Job Description

Senior Mobile Application Engineer (Kotlin/Jetpack/Swift) Location: Downtown Chicago (Hybrid) Employment Type: Contract to Hire, W2 only

We are seeking a versatile and highly skilled Senior Mobile Application Engineer with deep expertise in Android/iOS development and Java to join our innovative mobile team. In this pivotal role, you’ll serve as the bridge between our Android and iOS engineers, developing robust cross-platform solutions and modernizing mobile experiences for a global audience. The ideal candidate thrives in fast-paced environments, understands mobile architecture deeply, and is passionate about building high-performance, user-centric applications.

Key Responsibilities:

• Native Android/iOS expertise Role clarified to be focused on native development (Kotlin/Jetpack Compose for Android, Swift/SwiftUI for iOS).
• Legacy modernization experience Ability to deal with a 70% legacy codebase while introducing modern architecture patterns and better testability.
• Architecture mastery
  • 
    MVI & MVVM patterns for maintainable, scalable apps.
  • 
    Unidirectional data flow with ViewModels, State Flow, and dependency injection.
• Testing proficiency Comfortable with achieving high test coverage despite legacy code, using Espresso/XCUITest, mocking frameworks, and CI/CD pipelines.
• Security & compliance HIPAA-compliant development with strong encryption practices.
• AI/ML integration Adding AI-driven features like real-time transcription into healthcare apps.

Experience

• 
  Bachelor’s or Master’s degree in Computer Science, Engineering, or related field.
• 
  5+ years of professional mobile development experience, including recent work in cross-platform frameworks.
• 
  Proven success delivering and supporting mobile apps in production, particularly in global or enterprise environments.

Preferred Qualifications

• 
  Familiarity with Agile methodologies (Scrum, Kanban).
• 
  Experience using analytics platforms like Firebase or Google Analytics.
• 
  Knowledge of feature flagging and A/B testing strategies for global audiences.

Contract to Hire: This role offers the opportunity for full-time employment based on performance. CoSourcing Partners is an equal opportunity employer committed to fostering an inclusive and diverse workplace. We do not discriminate based on race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, veteran status, genetic information, or any other protected status under applicable federal, state, or local laws. We believe in creating a work environment where all employees feel valued, respected, and empowered to contribute to our success. Accommodations are available upon request for applicants with disabilities throughout the hiring process. Join us and be part of a team that values diversity, equity, and inclusion.