SF Symbols are Apple's vector symbol format. The OS ships with thousands of them, but you can make your own for your own apps.
The recommended way to make SF Symbols is to export a template from Apple's helper app, edit it in a vector editor, then re-import it and tag all the SF Symbol specific metadata.
This process is usually a pain in the ass. SF Symbols support multiple weights -- you draw three, and Apple interpolates between them. This means that each of your weights needs to have the same paths in the same order, with the same number of points. Everything has to be converted to outlines for the interpolation to work, it doesn't render strokes.
McKinley is my attempt to save you from that. It's a vector editor that is built around the constraints of SF Symbols. You can edit your symbol while flicking between the three weights or the four colour modes. It can save SF Symbol files or sync straight to Xcode asset catalogs. You don't have to bounce between a vector editor and a symbols converter, because McKinley is both.
I'm pleased with how live previews work. I wanted to offer a preview with Apple's own renderer. But you can't load an SF Symbol in-memory at runtime. So I figured out the file format for asset catalogs, and create a temporary one and load _that_. (I blogged about how I did it: https://www.amyworrall.com/blog/previewing-sf-symbols-with-a... )
A couple of things I know people will ask:
* It's a native AppKit app (not Electron or anything cross-platform) * Sold directly from my site via Stripe, not Mac App Store. * One-time purchase. License is valid on up to 5 computers, and covers all version 1.x updates. * There's a 14 day free trial, which includes saving/exporting * It is sandboxed, notarised, and all that good stuff * No analytics or network traffic, apart from updates (handled by Sparkle) and license checking (handled by Amore).
Happy to answer any questions or dive into technical details if people want :)