I help Dr. Uwe Risse DG2YCB with the compilation and distribution of WSJT-X Improved, more specifically by compiling WSJT-X Improved for Macs with Apple chips. I run MacOS 15.1 on my 2023 MacBook Pro with an M2 chip. I have an Apple Developer ID for which I pay $149 per year. The Developer ID permits me to sign an app for MacOS and also submit it to Apple for notarization. Notarization is the process Apple uses to ensure that the app doesn't have malicious content. Once an app is notarized, the developer can "staple" the notarization approval to the app. If all works correctly, Gatekeeper should see the approval and permit you open it without further action. There is no requirement that the app be distributed through the App Store, in fact, WSJT-X Improved for M1 apps are distributed through SourceForge like many other apps. All of the software I use in the compilation process including Cmake, QT, GCC and a number of Homebrew based programs work without issue on MacOS 15.1. If I install an app that evokes a complaint from Gatekeeper, I go to System Settings > Privacy and Security > Security and tell it to allow applications from anywhere, give them my fingerprint and I'm good to go. In my view, upgrading to MacOS 15 is not as onerous as it sounds.?