Nitro

An async-first Python web framework with its server compiled in.

# routes.py
from nitro.routing import HTTPRoute
from nitro.protocols import HttpRequest, HttpResponse, JSONResponse


async def show_user(request: HttpRequest, user_id: int) -> HttpResponse:
    return JSONResponse({"id": user_id, "name": "Ada"})


patterns = [
    HTTPRoute("/users/<int:user_id>", show_user, name="user"),
]

# app.py
from nitro import Nitro

app = Nitro(routes="routes")

nitro app:app

A project usually points the ROUTES setting at its route module rather than naming it here. Handlers can also be registered on the application directly with @app.route(...).

Installation

pip install nitro-framework

Python 3.13 or newer. The distribution is named nitro-framework; the package it installs is nitro, which is what you import. The wheel carries the compiled server, so there is nothing to build.

Extras pull in the clients particular backends need:

pip install "nitro-framework[redis]"

aws, azure, email-oauth, memcached, redis, sendgrid, and all.

nitro-intercom is published from this repository too, from the same tag and at the same version, so either package at a given version was built from the same source. A Nitro project does not install it — see docs/intercom.md.

Not an ASGI framework

Nitro does not implement ASGI and does not ship an adapter for it. The server — HTTP/1.1, HTTP/2, HTTP/3, WebSocket and WebTransport — is part of the package and calls your application directly.

That is a design choice rather than an omission. An intermediate protocol limits a server to what the protocol can express and charges every request for a translation into dictionaries and callables. Removing it is what lets routing, header handling, file serving, range requests and streaming backpressure live in compiled code while handlers stay ordinary Python coroutines.

The trade is worth stating plainly: a Nitro application runs on the Nitro server. It cannot be deployed under Uvicorn or Hypercorn, and it cannot mount an ASGI application inside itself.

Documentation

Start with the overview.

Layout

The two core crates know nothing about Python. Everything that needs an interpreter goes through a trait the binding crate implements, which is what keeps the whole request path testable without one.

Development

python -m venv .venv && . .venv/bin/activate
pip install maturin
maturin develop --extras dev          # builds the extension into the venv

cargo test --workspace                # Rust
pytest                                # Python
(cd nitro-intercom && pytest)         # the standalone package

Tests that need Redis skip when there is not one reachable at 127.0.0.1:6379, so a checkout without it still runs green.

Contributing

See CONTRIBUTING.md for how to get set up and what CI will check. Security issues go to SECURITY.md rather than the issue tracker. Changes worth knowing about are in CHANGELOG.md.

License

Licensed under either of Apache License, Version 2.0 or the MIT license, at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project by you shall be dual licensed as above, without any additional terms or conditions.

Copyright 2026 Jaldis B.V.