Comment by syrusakbary

Thanks for chiming in!

> it is worth noting that by using those older versions you will also be using older Pyodide versions too

Yeah, I think this summarizes properly the issue I mentioned. Basically compat flags are a global version that affects not only the Python version used but workerd as well. I believe you'll see some architectural issues from this design. Following up on your example, users will not be able to use a previous version of Python that has JSPI included, unless you update the old workerd as well (please correct me if I'm wrong), which will make certain things a challenge as workerd evolves.

> We wrote about cold starts (and sharding) in a previous blog post[2] which includes some numbers

Thanks for sharing. On that blogpost [2] Cloudflare Python Workers startup time was reported to be about 1.027 seconds, which is way behind the numbers we have at Wasmer for cold starts in Python apps (60ms, or 16x faster). That's why I was asking if you guys remeasured and have better timings now :)