prefab-ui

library0.19.1pypypi✓ verified 84d ago

Prefab is a generative UI framework for Python by PrefectHQ. It allows building interactive web UIs with pure Python, using reactive components. Current version: 0.19.1, requires Python >=3.10. Release cadence is active with frequent minor/patch releases.

web-framework

pip install prefab-ui

github ↗package ↗homepage ↗docs ↗

INSTALL

IMPORT

SIG · PREFAB-UI

prefab-ui

web-frameworkpythonv0.19.1

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

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

PrefabApp

✓ from prefab_ui import PrefabApp

✗ import prefab

Minimal app with a button, served locally.

import prefab from prefab import App, components app = App( components.Button(text="Hello, World!") ) if __name__ == "__main__": app.serve()

Debug

Known issues

gotchaImport as `prefab` not `prefab_ui` – the PyPI package name and import name differ.

fix

Use `import prefab` or `from prefab import ...`

affects: all

gotchaComponents must be imported from `prefab.components` submodule, not directly from `prefab`.

fix

Use `from prefab.components import Button, Form, ...`

affects: >=0.16.0

gotchaReactive state management requires understanding `prefab.state` and reactive variables; misuse can cause silent UI failures.

fix

Use `prefab.state.State` or `prefab.state.Reactive` for mutable state.

affects: all

gotchaThe `Form.from_model` runtime prefill feature was added in v0.19.1; earlier versions do not support `defaults` kwarg.

fix

Upgrade to 0.19.1+ or implement prefill manually.

affects: <0.19.1

gotchaCharts default to `show_legend=True` only from v0.17.0+; earlier versions had no legend.

fix

Upgrade to 0.17.0+ or set `show_legend=True` explicitly.

affects: <0.17.0

Upgrade

Version history

0.19.1latest on PyPI · released Apr 14, 2026

Audit

Dependencies

prefectoptionalPrefab is built by PrefectHQ and often used alongside Prefect workflows, but not required.

pydanticrequiredUsed for form models and data validation.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/PrefectHQ/prefab ↗

packagehttps://pypi.org/project/prefab-ui/ ↗

homepagehttps://prefab.prefect.io ↗

docshttps://prefab.prefect.io ↗