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I'm a Senior iOS Engineer and Technical Lead with 15+ years building high-performance, consumer-facing mobile applications shipped to millions of users across fintech, banking, insurance, telecom, and healthcare. I lead a team of 15 iOS engineers shaping architecture, raising the quality bar, and driving on-device AI adoption for a major UK retail banking group. I bring deep product observation — I study how the best apps work, notice details that make experiences feel effortless, and apply those insights to everything I build. Active open-source contributor building Arbiter, a unified AI runtime for Swift. I care about craft, I ship fast, and I make the people around me better. My work spans modern Swift (SwiftUI, async/await, Combine), on-device AI and ML (CoreML, MLX Swift, LLM integration), scalable architecture (MVVM, Clean Architecture), and hands-on delivery from concept through App Store release. I’m also shaping on-device AI ecosystems and mentoring engineers to elevate the whole team.…I'm a Senior iOS Engineer and Technical Lead with 15+ years building high-performance, consumer-facing mobile applications shipped to millions of users across fintech, banking, insurance, telecom, and healthcare. I lead a team of 15 iOS engineers shaping architecture, raising the quality bar, and driving on-device AI adoption for a major UK retail banking group. I bring deep product observation — I study how the best apps work, notice details that make experiences feel effortless, and apply those insights to everything I build. Active open-source contributor building Arbiter, a unified AI runtime for Swift. I care about craft, I ship fast, and I make the people around me better. My work spans modern Swift (SwiftUI, async/await, Combine), on-device AI and ML (CoreML, MLX Swift, LLM integration), scalable architecture (MVVM, Clean Architecture), and hands-on delivery from concept through App Store release. I’m also shaping on-device AI ecosystems and mentoring engineers to elevate the whole team.

Sanjay Kumar

App Developer, Web Developer, Programmer, +2

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I'm a Senior iOS Engineer and Technical Lead with 15+ years building high-performance, consumer-facing mobile applications shipped to millions of users across fintech, banking, insurance, telecom, and healthcare. I lead a team of 15 iOS engineers shaping architecture, raising the quality bar, and driving on-device AI adoption for a major UK retail banking group. I bring deep product observation — I study how the best apps work, notice details that make experiences feel effortless, and apply those insights to everything I build. Active open-source contributor building Arbiter, a unified AI runtime for Swift. I care about craft, I ship fast, and I make the people around me better. My work spans modern Swift (SwiftUI, async/await, Combine), on-device AI and ML (CoreML, MLX Swift, LLM integration), scalable architecture (MVVM, Clean Architecture), and hands-on delivery from concept through App Store release. I’m also shaping on-device AI ecosystems and mentoring engineers to elevate the whole team.…I'm a Senior iOS Engineer and Technical Lead with 15+ years building high-performance, consumer-facing mobile applications shipped to millions of users across fintech, banking, insurance, telecom, and healthcare. I lead a team of 15 iOS engineers shaping architecture, raising the quality bar, and driving on-device AI adoption for a major UK retail banking group. I bring deep product observation — I study how the best apps work, notice details that make experiences feel effortless, and apply those insights to everything I build. Active open-source contributor building Arbiter, a unified AI runtime for Swift. I care about craft, I ship fast, and I make the people around me better. My work spans modern Swift (SwiftUI, async/await, Combine), on-device AI and ML (CoreML, MLX Swift, LLM integration), scalable architecture (MVVM, Clean Architecture), and hands-on delivery from concept through App Store release. I’m also shaping on-device AI ecosystems and mentoring engineers to elevate the whole team.

Available to hire

I’m a Senior iOS Engineer and Technical Lead with 15+ years building high-performance, consumer-facing mobile applications shipped to millions of users across fintech, banking, insurance, telecom, and healthcare. I lead a team of 15 iOS engineers shaping architecture, raising the quality bar, and driving on-device AI adoption for a major UK retail banking group. I bring deep product observation — I study how the best apps work, notice details that make experiences feel effortless, and apply those insights to everything I build.

Active open-source contributor building Arbiter, a unified AI runtime for Swift. I care about craft, I ship fast, and I make the people around me better. My work spans modern Swift (SwiftUI, async/await, Combine), on-device AI and ML (CoreML, MLX Swift, LLM integration), scalable architecture (MVVM, Clean Architecture), and hands-on delivery from concept through App Store release. I’m also shaping on-device AI ecosystems and mentoring engineers to elevate the whole team.

Skills

Experience Level

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Hindi

Advanced

Panjabi, Punjabi

Advanced

Indonesian

Advanced

Work Experience

Lead Mobile Application Developer at Publicis Sapient

November 1, 2021 - Present

Led a team of 15 iOS engineers across three brand apps serving millions of users. Shaped modular architecture (MVVM, Clean Architecture), championed SwiftUI adoption and Swift Concurrency, and implemented on-device AI features. Built and shipped Slingshot, an AI-powered macOS developer tool that integrates LLMs into Xcode with prompt engineering, RAG pipelines, and agentic AI workflows. Drove product discovery with competitor analysis, identified patterns that delight users, and applied insights to Loyalty Wallet and Travel Hub to improve onboarding and revenue. Strengthened crash analytics, performance profiling, automated testing (XCTest, XCUITest, TDD), and CI/CD with Fastlane. Enforced security best practices (Keychain encryption, secure auth) and accessibility (VoiceOver, Dynamic Type) across the platform. Mentored engineers through architecture reviews and pairing to foster craft and continuous improvement.

Manager, Mobile Applications at Tech Mahindra (Client: British Telecom)

October 1, 2019 - November 1, 2021

Led iOS development for MyBT, driving UX improvements and delivering a native-to-Flutter transformation with pragmatic native-vs-cross-platform trade-offs. Drove performance improvements using Combine and WebSockets, implemented two-step secure authentication, and established engineering standards that improved quality and delivery cadence. Mentored teams across onshore and offshore locations, promoting clean architecture, testing discipline, and product-minded engineering.

Module Lead at Tech Mahindra (Client: Allianz Insurance)

March 1, 2016 - September 1, 2019

Architected modular iPad apps using VIPER/SOLID, analyzed and simplified complex insurance forms via dynamic JSON-driven rendering, and led Obj-C to Swift transformation. Implemented TDD achieving 90%+ test coverage, integrated RESTful APIs with CoreData offline persistence, and localized applications for the Indonesian market; Allianz won an innovation award for the work.

Senior iOS Developer at Tech Mahindra (Clients: Unilever, Doha Bank, Roche Pharma)

March 1, 2014 - February 1, 2016

Delivered consumer apps across retail, banking, and pharma with secure payment/auth flows and CoreData persistence. Led Obj-C to Swift migration, localization efforts, and maintained strong collaboration with cross-functional teams; received Best Team and Best Associate awards for performance.

Senior iOS Developer at Seasia Infotech

April 1, 2013 - February 1, 2014

Built a real-time hospital communication platform using XMPP and WebSockets with chat, group messaging, and media sharing. Implemented iBeacon and Bluetooth LE for location services, contributing to a 20% increase in user engagement.

Senior iOS Developer at SimPalm

April 1, 2012 - April 1, 2013

Shipped multiple fintech iOS applications with payment SDK integration and card-based processing. Implemented IoT hardware accessory communication for connected payment peripherals and mentored a team of 5 developers.

iOS Developer at Interworld Commnet

June 1, 2010 - April 1, 2012

Developed and launched multiple iOS applications across utility, entertainment, and retail. Reduced new hire onboarding time by 50% through structured training programs and improved app stability through systematic debugging processes.