What, Is the GIL?

One thing I find interesting about the GIL is how it mirrors a pattern you see in a lot of systems: the abstraction suggests parallelism, but the actual execution layer enforces a single path at critical points.

You end up debugging “why isn’t this scaling” while the real constraint isn’t visible at the API level. I’ve seen similar behavior in networked systems where things look nondeterministic, but are actually shaped by a hidden execution bottleneck underneath.