Robyn

0.84.0 verified Mon Apr 27 auth: no python

A super fast async Python web framework with a Rust runtime. Version 0.84.0, released recently; active development with monthly releases.

pip install robyn

Common errors

error RuntimeError: Robyn must be started with app.start() or app.run() ↓

cause Calling app methods like app.add_route() after app.start() has been called, or not calling start/run at all.

fix

Ensure you call app.start(port=...) once at the end of your script, and do not add routes after that.

error ImportError: cannot import name 'Robyn' from 'robyn' ↓

cause Outdated Robyn version or wrong import path (e.g., using `from robyn import robyn`).

fix

Upgrade robyn: pip install --upgrade robyn. Use from robyn import Robyn.

error AttributeError: 'NoneType' object has no attribute 'send' ↓

cause Async handler not returning a response, or returning None.

fix

Ensure every async route handler returns a string, dict, or Response object.

breaking Robyn requires a Rust toolchain to compile if installing from source; the pip wheel should be pre-compiled for common platforms. ↓

fix Use a pre-built wheel from PyPI; if building from source, install Rust via rustup.

gotcha The app instance must be passed `__file__` (or a string path) as the first argument. Omitting it causes an error. ↓

fix Always use `app = Robyn(__file__)` or `Robyn('MyApp')`.

deprecated The `@app.route()` decorator without an explicit HTTP method is deprecated; use `@app.get()`, `@app.post()`, etc. ↓

fix Replace `@app.route('/path')` with `@app.get('/path')`.

Robyn
wrong
```
import robyn
```
correct
```
from robyn import Robyn
```
Robyn class is the main app class; direct import of robyn module gives you the module object, not the class.
Request
wrong
```
from robyn.request import Request
```
correct
```
from robyn import Request
```
Request is a top-level import; there is no robyn.request submodule.
jsonify
wrong
```
from robyn.response import jsonify
```
correct
```
from robyn import jsonify
```
jsonify is exposed at package level; submodule paths are considered private.

Minimal Robyn web server with one route.

from robyn import Robyn

app = Robyn(__file__)

@app.get("/")
async def hello(request):
    return "Hello, world!"

app.start(port=8080)