TTX/FontTools is a suite of tools for manipulating fonts. It is written in Python and has a BSD-style open-source licence.
The flagship is TTX, a tool to convert OpenType and TrueType font files to an XML-based format (also called TTX), and back. This lets you edit TTF or OTF files with any text editor.
The FontTools library currently reads and writes TrueType font files, reads PostScript Type 1 fonts and more.
TTX/FontTools’ functionality is aimed towards font developers and font tool developers. It can of course be used to just access fonts (outlines, metrics, etc.) but it is not optimized for that. It will be further developed so it can be the core of any font editor. And that’s exactly what it will be for our upcoming major rewrite of RoboFog, our (commercial) PythonPowered font editor for MacOS.