Simpy

This is your go-to for modeling discrete-event systems where entities compete for shared resources over time. Think customer queues, manufacturing lines, network traffic, or logistics systems. It's built on Python generators, so processes read naturally: yield to wait, request resources with context managers, and SimPy handles all the event scheduling. The framework gives you Resources for servers, Containers for bulk materials, and Stores for object pools, plus all the monitoring hooks you need to extract wait times and utilization stats. If your system has irregular events and resource contention rather than continuous differential equations, this is the right abstraction. The learning curve is gentle if you understand generators.