opentype.js
Read and write OpenType fonts using JavaScript
...It allows you to access the letterforms of text from the browser or node.js. Once you have the shapes, you can modify them, for example by snapping them to a virtual grid. opentype.js provides you with raw access to the glyphs so you can modify them as you please. Create a bézier path out of a piece of text. Support for composite glyphs (accented letters). Support for WOFF, OTF, TTF (both with TrueType glyf and PostScript cff outlines) Support for kerning (Using GPOS or the kern table). Support for ligatures. Support for TrueType font hinting. ...