Who uses culsans?

[x42005e1f]

As the creator of an unpopular project, I am happy when someone starts using it. But, unfortunately, I have not found any ready-made tools that reliably show even public dependents. So I decided to start this discussion.

Here, I will talk about direct dependents that I found on the Internet and how they use culsans. I invite everyone who wants to join, especially those who use the project privately or on platforms where it is difficult to find any information (such as GitLab).

[x42005e1f]

academy-agents/academy (2025-06-27 – present; active)

A multi-agent system with asyncio support, built on the actor model. It uses Culsans queues both for communication between different event loops (in different threads) in the local exchange and as a backport of the shutdown() method.

[x42005e1f]

Vizonex/aiointernal (2025-08-06 – present; inactive)

A worker thread implementation with an asyncio interface, which delegates the execution of selected methods. It uses Culsans queues for communication between the asyncio thread and the worker thread.

[x42005e1f]

fxtelekom/PokieStream (2025-08-15 – present; inactive)

A network packet logger running on asyncio. It uses Culsans as a replacement for Janus to communicate between the main thread and a synchronous scapy sniffer running in a separate thread.

[x42005e1f]

feuerstein-org/bergtalzug (2025-08-17 – present; active)

An ETL pipeline implementation running on asyncio. It uses Culsans queues to transfer data between stages.

[dodofarm]

Glad you found it! If you recall we actually discussed implementation details in regard to the pipeline architecture in a discussion thread. Specifically about how to integrate the different types of executors.

I plan to add a feature to adjust the number of workers per pipeline stage (as well as size of the queue feeding the stage - culsans queue) sooner rather than later which is where culsans will be a real benefit.

Feel free to comment on the implementation if you find the time! For now all the code is in one single file :)

[x42005e1f]

Feel free to comment on the implementation if you find the time! For now all the code is in one single file :)

1. What is asyncio.Lock used for in ItemTracker? None of the code blocks for which it is used yield back to the event loop (they have no await), so their concurrent execution is impossible, which means that the lock is actually no-op.
2. The code for closing queues would be relevant for something like janus<1.2.0 (starting with 1.2.0, it provides aclose()), but Culsans queues do not create new tasks and therefore do not require any closing.
3. The shutdown code can be greatly simplified using the shutdown() method (added in Python 3.13, and also provided by Culsans since 0.1.0 for all supported versions of Python). By default, it does something similar to what your code does, but does not require special handling of None. I recommend looking at the API reference.

[dodofarm]

Thanks for your time! Sorry for the late response, had a busy week. I've just pushed the changes you suggested.

1. I realized since my code in ItemTracker never yields control there's no point in the lock since the GIL would never be released anyway.
2. Yep, removed the redundant closing code.
3. I actually saw the shutdown() method but decided not to use it so that later I can reduce the number of workers per stage dynamically. E.g. by sending 10 poison pills into a pool of 50 workers I would get it down to 40 workers gracefully. If I shut down the queue it would kill all the workers. Although I suppose in the current state since the dynamic reduction is not implemented yet I could just use Culsans shutdown() method...

If you have any other comment in terms of the pipeline design I'm happy to hear it. This is one of my first projects related to concurrency and asyncio specifically. Appreciate that you took some time to take a look!

Good luck with your project.

[x42005e1f]

Dewey-Data/deweypy (2025-09-05 – present; active)

A data hub client with asyncio support for downloading datasets. It uses Culsans queues to perform logging from different threads.

[x42005e1f]

vllm-project/guidellm (2025-09-29 – present; active)

A toolkit for evaluating LLM performance. It uses Culsans queues to implement a unified sync/async interface over shared data.

[x42005e1f]

fl2o/catflap-prey-detector (2025-10-26 – present; inactive)

A cat flap control system based on object detection. It uses Culsans queues to send images to the main asyncio event loop from a synchronous object detection tracker running in a separate thread.

[x42005e1f]

finecode-dev/finecode (2025-11-28 – present; active)

A tool runner with VSCode integration. It uses Culsans queues in the implementation of a JSON-RPC client for communication between different threads with multiple asyncio event loops.