iOS Developer (Frontend SDK)

About the Role:

The client is seeking a highly skilled iOS Developer with strong expertise in building Frontend SDKs for high-scale, secure, and high-performance mobile applications. In this role, you will design, develop, and optimize iOS SDK components that power client’s next-generation payment experiences, digital wallets, authentication frameworks, and secure transaction flows.

You will collaborate closely with product managers, architects, backend platform teams, and client’s global developer ecosystem to build best-in-class mobile SDKs used by merchants, partners, and financial institutions worldwide.

Key Responsibilities:

• SDK Design & Development:

• Design, develop, and maintain iOS Frontend SDKs using Swift and/or Objective-C.
• Build reusable client-side libraries, UI components, and frameworks for client’s mobile payment solutions.
• Ensure SDKs are lightweight, modular, scalable, and seamless for third-party integration.

• Integration & APIs

• Integrate payment APIs, authentication APIs, and secure transaction services.
• Work with RESTful APIs, JSON data structures, and backend engineering teams to ensure smooth communication between systems.
• Provide technical support for internal and external partners integrating iOS SDK.

• Performance & Security:

• Optimize mobile SDK performance, startup time, and memory usage.
• Implement highly secure coding practices aligned with PCI-DSS and client’s internal compliance.
• Work with encryption modules, secure storage, tokenization, and device authentication.

• Testing & Documentation:

• Develop automated unit tests, UI tests, and integration tests for SDK reliability.
• Create comprehensive developer documentation, integration guides, and sample apps.
• Support continuous integration/continuous deployment (CI/CD) pipelines for SDK releases.

• Cross-Functional Collaboration:

• Partner with product, design, and architecture teams to define mobile-first solutions.
• Participate in code reviews, sprint planning, and Agile ceremonies.
• Provide mentorship to junior developers and contribute to engineering best practices.

Required Skills & Qualifications:

Technical Skills:

• 10+ years of iOS development experience.
• Expert-level proficiency in Swift; working knowledge of Objective-C.
• Strong experience designing or maintaining mobile SDKs / frameworks.
• Hands-on experience with:
• Xcode, Instruments, XCTest
• Swift Package Manager / CocoaPods / Carthage
• REST APIs & JSON parsing
• Mobile security mechanisms (Keychain, certificates, OAuth, tokenization)
• Memory management, performance tuning, multithreading (GCD/OperationQueue)

Domain Skills:

• Exposure to payment systems, digital wallets, or fintech applications is highly preferred.
• Experience working with Visa, Mastercard, EMV, token services, or other payment ecosystems is a strong plus.

Soft Skills:

• Strong communication, documentation, and problem-solving abilities.
• Ability to collaborate in a fast-paced, cross-functional environment.
• Detail-oriented with a focus on secure and scalable engineering solutions.

Preferred Qualifications:

• Experience building SDKs adopted by large-scale developer communities.
• Knowledge of cryptographic libraries, secure enclave, or authentication frameworks.
• Familiarity with Agile, CI/CD, Git, Jenkins, or GitHub Actions.
• Bachelor’s or Master’s degree in Computer Science, Engineering, or related field.