Worked on the govuk-one-login/mobile-ios-common repository to enhance barcode scanning stability and error handling within iOS applications. Focused on improving the ScanningViewController by tightening error handling, refining cleanup routines, and addressing memory management issues related to view animations. Leveraged Swift and AVFoundation to implement robust capture session lifecycle checks, ensuring safe handling of multiple appearance cycles and reducing crash risk. Expanded unit testing coverage by updating mocks and lifecycle tests, which improved reliability in both production and continuous integration environments. The work resulted in a more stable barcode scanning experience and contributed to smoother CI workflows through targeted bug fixes.