“This script’s mission is simple: keep stem widths consistent while you fiddle with proportions of a glyph. It manages that by trying to compensate for scale deformations through interpolation. To do that, it requires at least two masters (a regular and bold for instance). This way, you can easily produce scaled versions of existing glyph for any purpose you see fit, small capitals, superiors, extended or condensed styles, scaled up, down, etc. Any transformation you input can be saved as a preset for a later use. Presets are stored inside the ufo file of the first master font (see below), but you can use presets stored in any of the open fonts available when using ScaleFast.” This extension shares many features with Frederik’s ufoStretch.