Thespian Actor Library VS gevent

"Even things that can't go wrong, do." - Troubleshooting Analog Circuits, Robert "Bob" Pease.

I had an application on a Raspberry PI that paired with a Bluetooth Low Energy device to fetch and send its data through a 3G dongle, on the premises of non-technical people who cannot troubleshoot, in different countries and time zones. There were a lot of things that could go wrong, and I wrote code to mitigate and recover, including pulling new code.

Part of it was using the Actor Model. I wrote actors to connect to the device, pulling data, sending data, computing what was sent, etc. The actor system handled the actors, when one died, it would recreate another one when an unhandled exception was met, for example.

https://en.wikipedia.org/wiki/Actor_model

If you're doing Scala, take a look at Akka. The new Scala has native support for this, if I remember correctly, without Akka.

If you're doing Python: https://github.com/kquick/Thespian, https://thespianpy.com/doc/

A sub-question for the folks here: is anyone using the combination of gevent and PyPy for a production application? Or, more generally, other libraries that do deep monkey-patching across the Python standard library?

Things like https://github.com/gevent/gevent/issues/676 and the fix at https://github.com/gevent/gevent/commit/f466ec51ea74755c5bee... indicate to me that there are subtleties on how PyPy's memory management interacts with low-level tweaks like gevent that have relied on often-implicit historical assumptions about memory management timing.

Not sure if this is limited to gevent, either - other libraries like Sentry, NewRelic, and OpenTelemetry also have low-level monkey-patched hooks, and it's unclear whether they're low-level enough that they might run into similar issues.

For a stack without any monkey-patching I'd be overjoyed to use PyPy - but between gevent and these monitoring tools, practically every project needs at least some monkey-patching, and I think that there's a lack of clarity on how battle-tested PyPy is with tools like these.

I'm not sure how much it replicates the CSP model, but the closest thing I've found to Go-style concurrency in Python is gevent: https://github.com/gevent/gevent

I personally still prefer to use it in all my projects.

Greenlet seems to have some troubles compiling with Python 3.9. https://github.com/gevent/gevent/issues/1627