forums.swift.org/t/featherview-a-native-mac-image-viewer-in-swift-6-that-opens-a-4-6-gb-psb-in-about-2-seconds/90411 Featherview: a native Mac image viewer in Swift 6 that opens a 4.6 GB PSB in about 2 seconds
Featherview is a free MIT-licensed macOS image viewer written in Swift 6; its PSB reader displays a 4.6 GB Andromeda image about two seconds after double-click, launch included. Its layer rendering matched Photoshop composites in 104 of 108 test files.
