A Python web framework that puts the static output first. File based routing, nested layouts, an HTML tag factory for components, Tailwind for styling, and htmx for just enough interactivity. Then a build step that prerenders your pages into plain HTML.
pip install koyoapp # once published
koyoapp create my-app
cd my-app
koyoapp dev
# open http://127.0.0.1:2309app/page.py maps to / out of the box. Add folders to build more routes; dynamic segments use bracket folders.
A layout.py anywhere in the tree wraps every page below it, composed inside the root layout.
koyoapp.html is a tag factory. Build reusable components in a components/ folder with Python functions.
globals.css compiles to koyo.css with your brand color, here the Koyo indigo #1800ad.
htmx 2.0 is vendored in. Pages can return fragments that swap into the DOM without a full reload.
use_state gives per-session in-memory values with increment and set actions.
Starlette, Uvicorn, watchfiles, typer, and tomlkit. That is the whole runtime footprint.
koyoapp build prerenders every static route to plain HTML with your assets and minified CSS.
Koyo is for developers who want to build a marketing site, a doc site, or an internal tool with plain Python, ship plain HTML, and avoid both a JavaScript framework on the server and a heavy frontend build chain.
State is deliberately simple and in memory, so Koyo is not the right fit when you need a database, user accounts, or multi-process sessions. See "State limitations" and the FAQ.