Mark Johnson
iOS Engineer
- Blacksburg, VA
- mjohnson@swdev.net
I have been using Objective C since the iPhone SDK was released.
When Swift was released at WWDC 2014 I immediately switched. I have been coding in Swift full time since 1.0 was released.
I was part of the iOS Foundation team at Square responsible for core libraries used by iOS developers at Square.
Languages/Formats: Swift, Objective C, C, JSON
APIS: SwiftUI, Swift Concurrency, Combine, UIKit, Apollo, NSURLSession, RxSwift, GraphQL, REST, Web Services, Foundation, libxml2, ReactiveSwift
Tools: Claude, Cursor, Xcode, Git, Tower, Visual Studio, Instruments, Slack
Square POS is one of the apps I worked on at Square.
Doximity is a previous app I worked on.
Amion is Doximity's scheduling app that I've worked on.
I'm helping Sandbar improve the architecture of their application
I helped modernize large Square libraries used by all iOS developers at Square.
In 2021 I helped enhance an athlete glucose monitoring app.
In 2019/20 I helped create and launch the Voice blockchain based social media iOS app.
I helped re-write Doximity's main application in Swift.
In 2017 I helped combine Doxmity's dialer app into their original main application.
In 2010 I helped create the client product on iOS in Objective C.
In 2016 I was the sole contributor on re-writing the iOS product in Swift.