Apple starts public beta for TestFlight for Mac. Using TestFlight for Mac developers could distribute beta version for macOS apps to testers.
TestFlight for Mac follows almost the same processes as TestFlight for iOS, so it should be familiar to developers.
Apple Developer: TestFlight 3.2 beta
Download: Beta Software Downloads
Developer:Try TestFlight for macOS beta for beta software distribution.
QA engineer:Try running beta apps from TestFlight for macOS.
PM/DM:Consider using TestFlight for macOS for apps beta usage.