The purpose of gevent is to bring the benefits of the async execution model to the preemptive multi-threading programming model. It achieves this goal admirably. However, there's no low level standard API for the C stack manipulation required to correctly support extension modules, so gevent is unlikely to ever become officially endorsed as part of the standard library. As a practical matter it's a hugely important piece of software (like Stackless Python before it), but that's a separate question from whether or not its appropriate for stdlib inculsion.