Veloce

Fast, ergonomic async Python web framework — ASGI-native, batteries included.

Documentation: veloceframework.com

Source code: https://github.com/Lokesh-Tallapaneni/veloce

Veloce framework (PyPI: veloceframework) is an ultra-fast async Python web framework — ASGI-native and batteries-included.

Veloce is a from-scratch async Python web framework. The router, request/response pipeline, dependency injection system, OpenAPI generator, WebSocket layer, and test client are all in-tree — not wrappers around an existing stack.

Position

Veloce is a from-scratch async Python web framework — not a wrapper around Starlette, FastAPI, or Flask. It provides FastAPI-style typed dependency injection, Pydantic v2 request/response validation, OpenAPI 3.1 schema generation, WebSocket support, and Flask-compatible helpers (g, flash, blueprints, session) in a single tree. It is built on a radix-tree router, an in-memory test client, and built-in CORS/CSRF/session/rate-limit/security-headers middleware. An external security review of the request path is planned ahead of 1.0; until then, treat it as pre-production software.

Key design points

• Async-first handlers. async def handlers run directly on the event loop; sync def handlers are supported transparently and run in a thread-pool executor so they do not block it.
• Precompiled dispatch. Handler signatures are inspected once at registration into a HandlerPlan; the per-request hot path performs no reflection.
• Radix-tree routing with typed path converters (int, float, string, uuid, path, date, datetime, time, timedelta, decimal, any, plus custom).
• Typed dependency injection via Depends, Security, SecurityScopes, including yield-style dependencies with teardown.
• OpenAPI 3.1 generated from Pydantic models, served through Swagger UI and ReDoc out of the box.
• In-memory test client drives the real ASGI surface — no sockets, no separate server process.

Requirements

Python 3.10+.

Veloce depends on orjson, httptools, pydantic v2, python-multipart, multidict, jinja2, and uvloop on non-Windows platforms.

Installation

pip install veloceframework

The installed package exposes the veloce import:

from veloce import Veloce

Example

Create main.py:

from veloce import Veloce

app = Veloce()


@app.get("/")
async def index() -> dict[str, str]:
    return {"hello": "world"}


@app.get("/items/{item_id:int}")
async def read_item(item_id: int) -> dict[str, int]:
    return {"item_id": item_id}

Run it:

veloce run main:app

veloce run serves under uvicorn when it is installed and falls back to the built-in server, which needs no extra dependencies. To pin the built-in server regardless, call app.run().

uvicorn is an optional extra — install it (pip install veloceframework[uvicorn]) to serve under it or any other ASGI server, or use app.run() / the gunicorn VeloceWorker:

uvicorn main:app

Open http://127.0.0.1:8000/items/42 to see {"item_id": 42}, or http://127.0.0.1:8000/docs for the interactive OpenAPI UI.

Feature surface

The full Tier 0/1/2 feature matrix and per-feature design notes live in docs/.

Project status

Veloce follows semantic versioning: the public API surface — the names exported from veloce/__init__.py — is what each release commits to. The current version is shown by the PyPI badge above.

Sponsor

Veloce is developed in the open. If it is useful to you, you can support its continued development through GitHub Sponsors.

License

MIT. See LICENSE.