Hypercorn

Rationale

Hypercorn  is the web server used by Fluid Attacks’ platform .

The main reasons why we chose it over other alternatives are:

• It is open source .
• It has full asynchronous programming  support, which is critical for performance.
• It supports both HTTP/2  and HTTP/3 ; this is critical for both security and performance.
• It has full parallelism  support, allowing us to have several workers within a single machine, which is critical for performance.
• It supports hot reloading, critical for the development experience.
• It seamlessly integrates with Starlette .

Alternatives

These alternatives were considered but not chosen for the following reasons:

Granian

• Granian  only supports HTTP/2 , which reduces security and performance.
• It is still a highly experimental project that could become relevant in the future.

Socketify.py

• Socketify  only supports HTTP/2 , which reduces security and performance.
• It only performs considerably faster when implemented as a framework, which would force us to also replace Starlette  with it, increasing complexity.
• Its fastest variants require us to use PyPy , increasing complexity.
• It does not support hot reloading, decreasing the development experience.

Uvicorn

• Uvicorn  only supports HTTP/1.1 , which reduces security and performance.
• It does not support parallelism , negatively impacting performance.

Gunicorn

• Gunicorn  requires implementing Uvicorn  for ASGI  support, thus inheriting most of the disadvantages mentioned before.
• We detected a high rate of 5XX HTTP errors when using it.

Usage

We use Hypercorn  as the web server for Fluid Attacks’ platform .