iOS developer with 5 years of experience building high-performance, user-focused applications. Skilled in Swift, SwiftUI, UIKit, and Core Data, with a strong focus on scalable architecture, clean code, and smooth user experiences. Experienced in collaborating with cross-functional teams to deliver features.

Yumi Okawa

iOS developer with 5 years of experience building high-performance, user-focused applications. Skilled in Swift, SwiftUI, UIKit, and Core Data, with a strong focus on scalable architecture, clean code, and smooth user experiences. Experienced in collaborating with cross-functional teams to deliver features.

Available to hire

iOS developer with 5 years of experience building high-performance, user-focused applications. Skilled in Swift, SwiftUI, UIKit, and Core Data, with a strong focus on scalable architecture, clean code, and smooth user experiences. Experienced in collaborating with cross-functional teams to deliver features.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate

Language

English
Advanced
Japanese
Fluent

Work Experience

Software Developer III (iOS) at TouchBistro
August 1, 2025 - September 8, 2025
Remote iOS software development: feature development with Swift and SwiftUI; performance optimizations, bug fixes, and writing tests in Swift and Objective-C; refactoring legacy code; participating in and leading technical design discussions.
Software Developer II (iOS) at TouchBistro
July 1, 2023 - September 8, 2025
Remote iOS development: feature development in Swift; performance improvements, bug fixes and test writing in Swift/Objective-C; ongoing performance tuning and test coverage.
iOS Developer & CI Automation at CGI
June 1, 2020 - September 8, 2025
Feature development for the CIBC mobile app; automated development pipeline and CI operations; developed an internal onboarding app.
iOS Developer & CI Automation at QuickMobile Inc.
May 1, 2016 - September 8, 2025
Feature development and performance improvements (Objective-C); bug fixes and unit tests; installed, configured and administered Jenkins automation; automated mobile test plan; created API and JavaScript implementations; designed and built UI test harness in Ruby; integrated Git/SVN hooks with JIRA.
iOS Developer (Contract) at Two Tall Totems
August 1, 2013 - September 8, 2025
Developed a social network app; fixed bugs for existing app using camera and location system.
iOS Developer & Systems Engineer (Contract) at Fifty Four Creative Inc.
May 1, 2013 - September 8, 2025
Consulted with clients and designed UI for iOS applications; managed external contractors to ensure timely delivery; enhanced features and fixed bugs in Objective-C as required.
Systems Engineer at Hitachi Business Solutions Co. Ltd.
July 1, 2003 - September 8, 2025
Consulted clients, designed GUI and interface; programmed in Visual Basic and C; designed/tested forms; installed and wrote manuals; integrated Cobol modifications for the Internal Revenue Service of Japan.
Software Developer III (iOS) at TouchBistro
August 1, 2025 - September 8, 2025
Feature development (Swift, SwiftUI); performance enhancements, bug fixes and writing tests (Swift, Objective C); refactor legacy code; participate/lead in technical design and discussions.
Software Developer II (iOS) at TouchBistro
July 1, 2023 - September 8, 2025
Feature development (Swift); performance enhancements, bug fixes and writing tests (Swift, Objective C); performance enhancements and writing tests.
iOS Developer & CI Automation at CGI
June 1, 2020 - September 8, 2025
Feature development for CIBC mobile app; automated a development pipeline and CI operation; developed an internal app to welcome people onboard.
iOS Developer & CI Automation at QuickMobile Inc.
May 1, 2016 - September 8, 2025
Feature development and performance enhancements (Objective C); bug fixes and unit tests (Objective C); installed, configured and administered Jenkins automation environment; automated mobile test plan, created API and JavaScript implementation; designed and built UI test harness in Ruby to run with Jenkins/CI test suite; programmed and integrated Git/SVN hooks with JIRA.
iOS Developer (Contract) at Two Tall Totems
August 1, 2013 - September 8, 2025
Developed social network app; fixed bugs for existing app using camera and location system.
iOS Developer & Systems Engineer (Contract) at Fifty Four Creative Inc.
May 1, 2013 - September 8, 2025
Consulted clients and designed UI for iOS applications; managed progress of external contractors to ensure timely delivery; enhanced features and fixed bugs in Objective C as required.
Systems Engineer at Hitachi Business Solutions Co. Ltd.
July 1, 2003 - September 8, 2025
Consulted clients, designed GUI and interface; programmed in Visual Basic and C; designed/tested forms, installed, and wrote manuals for the Internal Revenue Service of Japan; integrated systems and modified existing programs in Cobol for the Internal Revenue Service of Japan.
Early Childhood Educator at Cedardale Centre, Ltd.
June 1, 2012 - September 8, 2025
Planned and implemented activities for children aged 3-5 years; contributed to program development and daily care.
Early Childhood Educator at St. James Japanese Preschool
August 1, 2010 - September 8, 2025
Planned and facilitated a curriculum for the Japanese Immersion Program, including art, math, science and social studies; handled administrative duties including enrolment, parent meetings, meal planning and field trip planning and participation in community events.
Mathematics Tutor at Private Tutoring
March 1, 2001 - September 8, 2025
Tutored Algebra and Geometry to high school students.
Software Developer III (iOS) at TouchBistro
August 1, 2025 - September 8, 2025
Feature development (Swift, SwiftUI); Performance enhancement, bug fixes and writing tests (Swift, Objective C); Refactor the legacy code; Participate/lead in technical design and discussions
Software Developer II (iOS) at TouchBistro
July 1, 2023 - September 8, 2025
Feature development (Swift); Performance enhancement, bug fixes and writing tests (Swift, Objective C); Performance enhancement and writing tests
iOS Developer & CI Automation at CGI
June 1, 2020 - September 8, 2025
Feature development for CIBC mobile app; Automated a development pipeline and CI operation; Developed an internal app to welcome people onboard
iOS Developer & CI Automation at QuickMobile Inc.
May 1, 2016 - September 8, 2025
Feature development and performance enhancements (Objective C); Bug fixes and unit tests (Objective C); Jenkins automation; Automated mobile test plan, created API and JavaScript implementation; Designed and built UI test harness in Ruby to run with Jenkins/CI test suite; Programmed and integrated Git/SVN hooks with JIRA
iOS Developer (Contract) at Two Tall Totems
August 1, 2013 - September 8, 2025
Developed social network app; Fixed bugs for existing app using camera and location system
iOS Developer & Systems Engineer (Contract) at Fifty Four Creative Inc.
May 1, 2013 - September 8, 2025
Consulted clients and designed UI for iOS applications; Managed progress of external contractors to ensure timely delivery; Enhanced features and fixed bugs in Objective C as required
Systems Engineer at Hitachi Business Solutions Co. Ltd.
July 1, 2003 - September 8, 2025
Consulted clients, designed GUI and interface, programmed in Visual Basic and C, designed/tested forms, installed, and wrote manuals for the Internal Revenue Service of Japan; Integrated systems and modified existing programs in Cobol for the Internal Revenue Service of Japan
Mobile Software Developer III (iOS) at TouchBistro
August 1, 2025 - August 1, 2025
Feature development (SwiftUI, Swift) – Built new application features, including SwiftUI interface, database architecture and application logic with Swift; Integrated the kitchen display system with the POS; Refactored the legacy codebase into a modern and modular architecture; Performance enhancement, bug fixes, writing unit/UI tests (Swift); Contributed and led the design of technical solutions, ensuring scalable and maintainable architecture
Mobile Software Developer II (iOS) at TouchBistro
July 1, 2023 - July 1, 2023
Feature development (Swift) – Developed and maintained core POS features for a high-traffic iOS application; Performance enhancement, bug fixes and writing unit tests (Swift, Objective C)
iOS Developer & CI Automation at CGI
June 1, 2020 - June 1, 2020
Feature development for CIBC mobile app (Objective C); Automated a development pipeline and CI operation at CIBC; Developed an internal app to welcome people onboard
iOS Developer & CI Automation at QuickMobile Inc.
May 1, 2016 - May 1, 2016
Feature development and performance enhancements (Objective C); Bug fixes and unit tests (Objective C); Installed, configured and administered Jenkins automation environment; Automated mobile test plan, created API and JavaScript implementation; Designed and built UI test harness in Ruby to run with Jenkins/CI test suite; Programmed and integrated Git/SVN hooks with JIRA
iOS Developer (Contract) at Two Tall Totems
August 1, 2013 - August 1, 2013
Developed social network app Yumi Quint – Curriculum Vitae - Page 2 of 3; Fixed bugs for existing app using camera and location system
iOS Developer & Systems Engineer (Contract) at Fifty Four Creative Inc.
May 1, 2013 - May 1, 2013
iOS Developer & Systems Engineer (Contract); Consulted clients and designed UI for iOS applications; Managed progress of external contractors to ensure timely delivery; Enhanced features and fixed bugs in Objective C as required
Systems Engineer at Hitachi Business Solutions Co. Ltd.
July 1, 2003 - July 1, 2003
Consulted clients, designed GUI and interface, programmed in Visual Basic and C, designed/tested forms, installed, and wrote manuals for the Internal Revenue Service of Japan; Integrated systems and modified existing programs in Cobol for the Internal Revenue Service of Japan

Education

Associate of Engineering – Major in Information Science & Technology at Oshima National College of Maritime Technology
January 11, 2030 - September 8, 2025
iOS Application Development for iPhone and iPad at British Columbia Institute of Technology (BCIT)
January 11, 2030 - September 8, 2025
Java Application Development at British Columbia Institute of Technology (BCIT)
January 11, 2030 - September 8, 2025
Certified in Early Childhood Care Education at MTI Community College
January 11, 2030 - September 8, 2025
Completed one year of English language training at International House of Vancouver
January 11, 2030 - September 8, 2025
Certificate in iOS Application Development at British Columbia Institute of Technology (BCIT)
January 11, 2030 - September 8, 2025
Certificate in Java Application Development at British Columbia Institute of Technology (BCIT)
January 11, 2030 - September 8, 2025
Certificate in Early Childhood Care Education at MTI Community College
January 11, 2030 - September 8, 2025
English Language Training at International House of Vancouver
January 11, 2030 - September 8, 2025
Associate of Engineering – Information Science & Technology at Oshima National College of Maritime Technology
January 11, 2030 - September 8, 2025
iOS Application Development for iPhone and iPad at British Columbia Institute of Technology (BCIT)
January 11, 2030 - September 8, 2025
Associate of Engineering – Major in Information Science & Technology at Oshima National College of Maritime Technology
January 11, 2030 - September 8, 2025
Certified in Early Childhood Care Education at MTI Community College
January 11, 2030 - September 8, 2025
English Language Training at International House of Vancouver
January 11, 2030 - September 8, 2025
Certificate at British Columbia Institute of Technology (BCIT)
January 11, 2030 - November 18, 2025
Certificate at MTI Community College
January 11, 2030 - November 18, 2025
English Language Training at International House of Vancouver
January 11, 2030 - November 18, 2025
Associate of Engineering – Major in Information Science & Technology at Oshima National College of Maritime Technology
January 11, 2030 - November 18, 2025

Qualifications

Class 2 Information Technology Engineer (Japan)
January 11, 2030 - September 8, 2025
Class 2 Information Technology Engineer (Japan)
January 11, 2030 - September 8, 2025
Class 2 Information Technology Engineer (Japan)
January 11, 2030 - September 8, 2025
Class 2 Information Technology Engineer (Japan)
January 11, 2030 - November 18, 2025

Industry Experience

Software & Internet, Computers & Electronics, Financial Services, Professional Services, Media & Entertainment, Education, Retail, Other

Experience Level

Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate

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