Lead iOS Engineer – Mobile SDK Modernisation ( Lead I - Software Engineering)

Role description

Lead iOS Engineer – Mobile SDK Modernisation

Location: London / Leeds (Hybrid)

Type: Contract Inside IR35/ Fixer Term Employment

We are seeking a highly experienced Lead iOS Engineer to drive the technical design and implementation of our Mobile SDK modernisation programme. This role will play a critical part in defining the next-generation iOS architecture, shaping migration strategies, and establishing best-in-class engineering standards for scalable, secure, and enterprise-grade SDK development.

You will lead technical decisions, develop proof-of-concept components aligned to the target architecture, and enable engineering teams through strong standards, mentoring, and governance.

Key Responsibilities:

• Lead the architecture and design of iOS SDKs for enterprise-scale mobile platforms.
• Define and validate migration strategies toward modernised, future-ready SDK architecture.
• Develop proof-of-concept solutions to de-risk and validate architectural approaches.
• Establish and drive engineering standards across code quality, API design, testing, and distribution.
• Collaborate with cross-functional teams to ensure alignment with platform, security, and compliance requirements.
• Mentor engineers and promote a culture of technical excellence and continuous improvement.

Core Qualifications:

• Extensive hands-on experience in iOS development, including leading complex initiatives.
• Proven track record designing, building, and maintaining reusable iOS SDKs/frameworks consumed by external applications.
• Experience guiding teams through technical decision-making, code reviews, and engineering best practices.
• Exposure to enterprise or regulated environments is advantageous.

Technical Expertise:

• Swift & iOS Architecture: Strong expertise in Swift (including async/await and Combine) with solid Objective-C interoperability, and experience designing clean, stable public APIs.
• SDK & Framework Development: Proven experience building and distributing reusable iOS SDKs using XCFrameworks, Swift Package Manager, and/or CocoaPods, with an understanding of module stability and versioning.
• Performance & Optimisation: Ability to manage application footprint, optimise performance (launch time, memory, binary size), and maintain compatibility across iOS versions.
• Security & Compliance: Practical knowledge of iOS security best practices (e.g., Keychain, certificate pinning) and familiarity with privacy and App Store compliance requirements (e.g., ATT, data minimisation).
• Platform Capabilities: Understanding of iOS background execution, device capabilities (e.g., sensors), and associated constraints around performance, battery, and privacy.
• Testing & Quality: Strong testing practices using XCTest/XCUITest, with experience leveraging tools such as Instruments for performance analysis and diagnostics.
• Build & Distribution: Experience with code signing, provisioning, and managing distributed binaries across environments.

Hurry & Apply for a more detailed conversation!

#UST

Skills

solution architecture,cross functional,architectural standards,program transformation,

About UST
UST is a global digital transformation solutions provider. For more than 20 years, UST has worked side by side with the world’s best companies to make a real impact through transformation. Powered by technology, inspired by people and led by purpose, UST partners with their clients from design to operation. With deep domain expertise and a future-proof philosophy, UST embeds innovation and agility into their clients’ organizations. With over 30,000 employees in 30 countries, UST builds for boundless impact—touching billions of lives in the process.