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I'm aPrincipal iOS engineer with a passion for building scalable mobile platforms and delivering reliable experiences at scale. I own end-to-end platform strategy, engineering standards, and multi-team execution from design through release. I thrive on partnering with product, design, and backend teams to ship robust solutions that balance technical rigor with business outcomes. I enjoy mentoring engineers, driving automated testing and accessibility initiatives, and shaping architectures that enable fast, safe delivery across large codebases. My background spans iOS, data integration, and distributed systems, with hands-on experience across healthcare, education, retail, and manufacturing domains.…I'm aPrincipal iOS engineer with a passion for building scalable mobile platforms and delivering reliable experiences at scale. I own end-to-end platform strategy, engineering standards, and multi-team execution from design through release. I thrive on partnering with product, design, and backend teams to ship robust solutions that balance technical rigor with business outcomes. I enjoy mentoring engineers, driving automated testing and accessibility initiatives, and shaping architectures that enable fast, safe delivery across large codebases. My background spans iOS, data integration, and distributed systems, with hands-on experience across healthcare, education, retail, and manufacturing domains.

Douglas W. Sjoquist

App Developer, Architect, AI Prompt Engineer, +1

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I'm aPrincipal iOS engineer with a passion for building scalable mobile platforms and delivering reliable experiences at scale. I own end-to-end platform strategy, engineering standards, and multi-team execution from design through release. I thrive on partnering with product, design, and backend teams to ship robust solutions that balance technical rigor with business outcomes. I enjoy mentoring engineers, driving automated testing and accessibility initiatives, and shaping architectures that enable fast, safe delivery across large codebases. My background spans iOS, data integration, and distributed systems, with hands-on experience across healthcare, education, retail, and manufacturing domains.…I'm aPrincipal iOS engineer with a passion for building scalable mobile platforms and delivering reliable experiences at scale. I own end-to-end platform strategy, engineering standards, and multi-team execution from design through release. I thrive on partnering with product, design, and backend teams to ship robust solutions that balance technical rigor with business outcomes. I enjoy mentoring engineers, driving automated testing and accessibility initiatives, and shaping architectures that enable fast, safe delivery across large codebases. My background spans iOS, data integration, and distributed systems, with hands-on experience across healthcare, education, retail, and manufacturing domains.

Available to hire

I’m aPrincipal iOS engineer with a passion for building scalable mobile platforms and delivering reliable experiences at scale. I own end-to-end platform strategy, engineering standards, and multi-team execution from design through release. I thrive on partnering with product, design, and backend teams to ship robust solutions that balance technical rigor with business outcomes.

I enjoy mentoring engineers, driving automated testing and accessibility initiatives, and shaping architectures that enable fast, safe delivery across large codebases. My background spans iOS, data integration, and distributed systems, with hands-on experience across healthcare, education, retail, and manufacturing domains.

Skills

Experience Level

Expert

Expert

Expert

Intermediate

Intermediate

Language

English

Fluent

Work Experience

Principal Software Engineer (iOS Platform / Checkout) at Walmart

May 1, 2020 - Present

Owned iOS checkout platform architecture and delivery for Walmart’s high-volume eCommerce experience, partnering cross-functionally to ship reliable, scalable features at pace. Led architecture evolution, modularization, and long-term platform maintainability. Drove automated testing and accessibility training. Established comprehensive automated testing (unit, integration, UI) with XCTest/XCUITest, raising coverage and reducing post-release defects. Led multi-team delivery across a large inner-sourced codebase with frequent production releases. Defined and enforced iOS engineering standards for architecture, code quality, performance, security, and testing. Architected unidirectional, reactive iOS systems using Swift, Combine, and MVVM-styles patterns. Collaborated with backend teams on GraphQL schema design and mobile-optimized API integrations for checkout and payments. Drove observability and reliability initiatives, instrumenting core checkout flows and maintaining 99.9%+ crash-

Independent iOS Developer at Custom iOS App Development (Independent)

September 1, 2010 - Present

Developed and maintained over 20 custom iOS applications for healthcare, real estate, education, and consumer goods industries. Provided architecture guidance, automated testing, performance optimization, and client-focused delivery. Delivered specialized solutions including medical infusion tracking, attendee access control systems, conference guides, physical therapy support tools, and childhood learning apps.

Data Engineer & iOS Developer at McGraw Hill Education

June 1, 2022 - September 1, 2023

Integrated analytics tools into the iOS Sharpen App. Developed key features including settings, user onboarding, and authentication. Implemented and integrated seven tools for analytics, email and SMS automation, AWS data lake, and push notifications.

Senior iOS Engineer at WalmartLabs (ASDA, Sam's Club)

April 1, 2014 - May 1, 2020

Led team in refactoring checkout code to unidirectional, reactive architecture, modernizing the codebase and improving maintainability. Increased test coverage from under 50% to over 75%. Migrated from Objective-C to Swift, ensuring long-term technical sustainability. Implemented eCommerce features, supported millions of daily active users, and maintained legacy Objective-C modules across multiple app releases.

Independent Java/J2EE Contractor at Various industries: DoD, DARPA, Education, Mining, Retail

November 1, 1998 - June 1, 2013

Designed and developed manufacturing tracking systems in Java, optimizing production workflows and inventory management. Built HR workflow tools and distributed agent systems for research projects and enterprise environments.

Software Engineer at Synergy Inc/ICFI

May 1, 1996 - November 1, 1998

Designed and built proof-of-concept logistics systems for USAF research labs; contributed to planning tools and collaboration software for DoD initiatives.

Software Developer, Adjunct Instructor, Outside Consulting, Assistant Director of Computer Services at Cedarville College

January 1, 1982 - January 1, 1996

Supported academic and administrative software initiatives, delivered consulting projects, taught courses, and assisted in directing computing services at the college.