Font by Zaweba on Mac and Linux
The Mac and Linux versions of Font by Zaweba wrap the same interface and font compiler in an Electron shell, so fonts are made the same way on each system.

People who make fonts don't all use the same computer. A teacher might plan worksheets on a school laptop, a designer might work on a Mac, and someone who likes to tinker might run Linux at home. A font maker that works across those systems makes it easier to keep one project going wherever you are.
Font by Zaweba began on Windows, and Mac and Linux versions now exist alongside it. They use an Electron shell around the same interface and the same compiler. Electron is a well known way of packaging an app for several operating systems, and here it wraps the very screens and the very font building engine that the Windows version uses.
What being the same interface means
Because the interface is shared, everything you learn on one system carries over. The style stack, with its ordered operations for weight and contrast, width, corner rounding, serifs, decorations, cut-outs, shears, perspective, rotation, outline and pattern fill, works the same. So do the presets, the glyphs grid with its filters, the glyph editor with Skeleton and Outline modes, the spacing sliders and kerning pair editor, and the live preview.
You start from the same base alphabet of 109 characters. Your own components, imported as SVG or drawn in the component editor, behave the same way. A tutorial written about one version applies to the others.
What being the same compiler means
The compiler is the part that turns your design into font files. Sharing it means the TTF, OTF and WOFF2 files you export are built the same way on every system, and they go through the same checks for tables, overlaps and contour direction. A font you make on a Mac is the same kind of font as one made on Windows.
That matters if you move between machines or share work with someone else. A typeface for a small business might be started on one computer and finished on another, and the exported files will match what you'd expect from either.
Moving projects between systems
Projects are saved as .zfont files, which are ZIP files with a documented format. You can save a project on one system and open it on another, then carry on where you left off. Undo and redo cover style and glyph changes while you work.
If you edit letters outside the app, the SVG glyph sheet round trip works as a file exchange too: export every glyph as an SVG sheet, edit it in a vector editor, and import it back. Changed glyphs are flagged so you can review them.
Installing fonts on each system
On Windows, Install for me installs the font for the current user with no administrator prompt. The way fonts are installed differs from one operating system to another, so on a Mac or a Linux machine, install the exported files the way your system normally adds fonts. Once installed, a four-style family links Regular, Bold, Italic and Bold Italic as one family, so programs that use bold and italic buttons pick your real styles.
For a website, the web kit is the same everywhere: a folder with the WOFF2 files, a fonts.css of @font-face rules and an index.html demo page, ready to copy to a site. Web fonts don't care which computer made them.
Good to know
Font by Zaweba is free software under the EULA, works offline and needs no account, which is just as true on a Mac or Linux machine as it is on Windows. Fonts you make belong to you, and the licence you choose is written into the files.
If you already use Font on Windows, nothing changes about how you work. If you're on a Mac or Linux and have been looking for a way to make a typeface with sliders rather than drawing every letter, the same app is there for you.