Mac OS Device Programming Application

We require a Mac Big Sur compatible application to program SAMD21 devices via USB cable connectivity.
In the past we have advised customers to use BOSSA by Schumatech to install firmware updates to our product using a bin file. However, the process is cumbersome and prone to errors. Since the introduction of Big Sur, installing the BOSSA GUI app has become more difficult. We already have a Windows 10 bespoke update app (that incorporates Bossac) and therefore we now require the equivalent for Mac.

This page will show the functionality of the Windows App..
https://www.electrastim.com/pages/how-to-use-electrastim-update-software

We appreciate that Mac OS will attempt to block anything that is not on the App Store and can accept work-arounds such as authorisation via the Privacy & Security settings. Registering for the App Store is not a cost effective option.

The App must detect the presence of the device on the USB port and then program the update firmware file to it. Ideally the update binary file will be pulled from our ftp server and verified with SHA-256 in the same way as our Windows 10 App. The app must support two different hardware models selectable by the user which will then program the appropriate binary firmware update file.

Arduino uses the Bossac utility to program SAMD21 M0 ARM CORTEX devices.
The attached files shows the current Mac OS method and the Windows 10 method which is to be replicated for Mac OS with compatibility with Catalina and Big Sur as a minimum.