Hypercorn

Last updated: Oct 28, 2026

Rationale

These are the primary reasons why Fluid Attacks selected it:

It is open source.
It has full asynchronous programming support, which is very important for performance.
It supports HTTP/2 and HTTP/3. This support is very important for security and performance.
It has full parallelism support. Thus, Fluid Attacks can have more than one worker on the same machine, which is very important for performance.
It supports hot reloading, which is very important for the development experience.
It integrates easily with Starlette.

Fluid Attacks examined these alternatives, but it did not select them for these reasons:

Granian supports only HTTP/2, which decreases security and performance.
It is a very experimental project at this time. It can become important in the future.

Socketify supports only HTTP/2, which decreases security and performance.
It is much faster only as a framework. To use it as a framework, Fluid Attacks must also replace Starlette with it, and the complexity increases.
Its fastest variants must use PyPy, and the complexity increases.
It does not support hot reloading, which makes the development experience worse.

Gunicorn must use Uvicorn for ASGI support. Thus, it has most of the disadvantages above.
With Gunicorn, Fluid Attacks found a high rate of 5XX HTTP errors.

Fluid Attacks uses Hypercorn as the web server of the Fluid Attacks platform.