Since I started investigating my articles about Mojave's new fast-paced action, I've seen high and low for third-party examples. Although I have many apps installed here, the only quick actions I have been able to add are my own Automator workflows. Then I found an App Store app that offers an installable quick action: the amazing Yoink, by Matthias Gansrigler of Eternal Storms Software.
Matthias is a very experienced Mac developer who knows his way around macOS much better than I do. So – if he forgives me – in this article I will discover how he has managed to implement a quick action.
I was surprised that even though I have the current version of Yoink installed, I had no quick action from being available, according to the extension pane. So I ran Yoink and then in preferences, where I discovered that this is an optional installation.
 So when I clicked the button to install his quick action I was asked to approve it.
Perhaps this is a limitation imposed by the App sandbox where Yoink is running, I thought. I went ahead and installed it and tried it out. Yes, it works and works very well.
In addition, Yoink's quick action shows up in the expansion pane now, and can be activated or deactivated there. It was time to see and see how this was implemented, so I looked in / Library / Services, just to find that it still doesn't exist. is a Services folder in / System / Library, but it contains only some older workflows and other items that are not a
I found Yoink Quick Action in the Services folder in the Home Directory Library ~ / Library / Services, where it turns out be an Automator workflow.
Opening that in Automator reveals that it only breaks into a command with a line to open the Yoink app in the workflow. That's it.
So, if you want to build your own quick actions, my advice is to stick to Automator, though that may mean that you need to encapsulate the work code into a shell command and call it in your workflow. Trying to make a quick action using Objective-C or Swift, looks for the moment to be a big bet with little chance of success.
Perhaps some third-party apps out there, offer many more quick action, and I just harbor I haven't discovered them yet. Currently, except for three third-party Automator workflows, two of which I made myself, all I think is the standard bound action that comes with Mojave. Maybe others can't make their head or tail off, or just don't see their value.
Anyway, for Mojave, Quick Actions is the big new feature that hasn't happened.