Create macOS app scaffold using swift

We need to port an existing app to macOS 10.15 and 11. The authoring environment used before depends on 32 bit components and is gone, so a re-write using Swift is in order. What we seek is an experienced developer who can aid us in creating a scaffold to work with in that process. In principle the app shall:

- receive files and or folders by drag-n-drop onto the UI

- determine all files from dropped folders and their sub-folders

- process only files matching a set of file extensions (CR2 CR3 NEF PEF DNG RAF RW2 etc. etc.)

- using a not all that complex interface have a few check box and drop down options

- for each file programmatically create a command line script to call by Apple Script "do shell script" (all scripts exist and are not part of the scaffold)

- spawn the script and give back the shell immediately

- poll the file system like twice a second thereafter checking for a file created by the script indicating it is done

- spawn and monitor processing for as many files in parallel as there are CPU cores in the Mac

- clean up, await more files etc.

The app exists for 10.6 through 10.14 so exploring desired behavior is not a problem. The whole process will be guided in a detailed way, all it takes is profound experience with Swift / Cocoa / Objective C and it should work out fine.

Mac OS Objective C Cocoa Swift Bash Scripting

Project ID: #30650530

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