ufo2ft

library3.8.2pypypi✓ verified 84d ago

A Python library that compiles UFO (Unified Font Object) sources into OpenType font binaries (.otf and .ttf) using FontTools. Version 3.7.1 requires Python >=3.10. It bridges UFO data structures with FontTools' font compilation pipeline, supporting features like Mark-to-Mark positioning, kern feature generation, and variable font instantiation. Release cadence is irregular with patches every few months.

data

pip install ufo2ft

github ↗package ↗

INSTALL

IMPORT

SIG · UFO2FT

ufo2ft

datapythonv3.8.2

Install

3.2s avg

Import

—

Disk

50MB

Pass rate

5/ 10

Env Coverage5 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v3.8.2 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

build_error

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 3.2s · import 0.000s · 51MB

50MB installed

● package 50MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

compileOTF

✓ from ufo2ft import compileOTF

✗ from ufo2ft import compileInterpolatableFontFromUFOs

compileTTF

✓ from ufo2ft import compileTTF

compileVariableTTF

✓ from ufo2ft import compileVariableTTF

Compile a single UFO into an OpenType font file.

from ufo2ft import compileOTF from fontTools.ufoLib import UFOReader # Replace with actual path to your .ufo path = "path/to/font.ufo" reader = UFOReader(path) font = compileOTF(reader) font.save("output.otf") print("OpenType font saved.")

Debug

Known issues

breakingPython 3.9 dropped as of v3.7.0; requires Python >=3.10.

fix

Upgrade to Python 3.10 or higher.

affects: >=3.7.0

breakingIn v3.6.8, dependencies were pinned to exact versions, causing clashes. This was fixed in v3.6.9.

fix

Upgrade to v3.6.9 or later, or avoid pinning ufo2ft with exact constraints.

affects: 3.6.8 only

deprecatedSome internal modules like ufo2ft.outlineCompiler may change; rely on stable public API (compileOTF, compileTTF, compileInterpolatableFontFromUFOs).

fix

Use top-level imports from ufo2ft package.

affects: all

gotchaufo2ft works with both defcon and ufoLib2 for UFO objects, but v3.7.0 made neither strictly required. If using defcon, ensure it's installed separately.

fix

Install defcon explicitly if needed: pip install defcon.

affects: >=3.7.0

gotchaWhen compiling variable fonts, ensure all master UFOs have the same glyph set and consistent outlines; otherwise compilation may fail silently or produce incorrect data.

fix

Validate master UFOs before compiling with compileInterpolatableFontFromUFOs().

affects: all

Upgrade

Version history

3.8.2latest on PyPI · released Jun 15, 2026

Audit

Dependencies

fonttools[ufo,lxml,feaLib]requiredCore dependency for font compilation and feature processing

Agent activity

19 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/googlefonts/ufo2ft ↗

packagehttps://pypi.org/project/ufo2ft/ ↗