Best way to import variable font source

I want to make some edits to the open source font Source Sans

The font’s source files are available here, but I’m not sure how to best import it to Glyphs

There are poles, features, UFOs, etc. I’ve read this help doc, but it’s mostly related to opening font files.

Any help would be greatly appreciated. Thank you!

In the source files repo did you read the file? It has all the instructions.

From what I understand, those instructions are for building the release font files right?

I could just open the font files in Glyphs, but the instructions note that it would be reverse engineering the file and data would be lost. Therefore, editing from the source is the best option.

Since I have access to the source, I was trying to see how to use them in Glyphs

Open the UFOs doesn’t work?

Yes, the .ufo files work fine, once I found them. They are in the Main branch, not at the link @sixfingeredamish posted.

Wouldn’t that only open one master? I guess that’s fine if you only want to edit some outlines and then build from the command line.

But if you want to import the entire variable font source from a set of UFOs, you have to open the .designspace file in Glyphs. Glyphs makes this difficult as it doesn’t tell Finder that it can open these files. You have to go to Open With > Other, then switch the filter to All Applications, then choose Glyphs 3. Only follow this approach if you want to save your edits in a new .glyphs (or .glyphspackage) file. Glyphs cannot save your changes back to the designspace+UFO sources.


I fixed the opening of .designspace files. Thanks for the tip.