how are we going there ( fmp / fmgo )
A very interesting project, indeed. As long as it's not hobbled, it may well provide the solution to the deprecated runtime problem for macOS. (Marzipan is an acquired taste.)
Well, Marzipan is just a rumor, as far as I know. Recently FMI was quite open about the future development, have a look at this to get an idea on what is coming:
FileMaker Product Roadmap 2019
Rumor? Yes. But it's Apple's not FMI's.
As I understand, Marzipan is related to the swift ABI stability (ABI is expected to be ready by June 2018), ... where marzipan would become a reality in September 2018. (futurology)
FileMaker, as a subsidiary of Apple should be aligned to Marzipan. ... or not?
Marzipan confirmed for 2019 ?, ...app. iOS can be used in macOS,... is surely related to the release of swift 5 ABI stability.
Bringing Your Apps to the New iPad Pro - Tech Talks - Videos - Apple Developer
Please remember that this is a technology for developers.
It looks like we get the UIKit framework for Mac, so a developer could modify his iOS app with some additions like a menubar and build a Mac app from an iOS project in Xcode.
So if FileMaker Inc. wants to use this to bring FM Go to the Mac, they could do it.
But it may be easier to make a FMP without editing capabilities and put it on the Mac App Store as free download to connect to FMS.
Marzipan will bring certain parts of UIKit (iOS dev) over to AppKit (macOS dev). It's already "here", in that Apple is currently using it in some of their macOS apps like "News", "Stocks", and "App Store", included with macOS Mojave. Those are all Marzipan apps. When the Swift 5 betas start arriving prior to WWDC (June), support for it should be available to developers.
I've been making Swift (iOS) apps that use the FileMaker Data API, so I'm pretty excited about being able to create custom thin client apps for macOS.
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