[dualogy]

> I discovered Waitgroups during the project

Don't know about your exact map use-case you had at hand, but generally speaking the Mutexes suffice for Lock()ing/Unlock()ing a resource that is accessed concurrently, whereas the WaitGroups serve usually best to just fire off a couple of parallel jobs (that don't access any shared-between-them resources) and then simply Wait() for them all to finish. No real protection from concurrent accesses in there, other than for the WaitGroup's own hidden internal counter that's used to Wait()

Of course these are the low-level sync primitives, channels are the higher-level abstraction, but the former can take you far --- sometimes the latter are the sanest/only choice of course. Especially for parallel goroutines needing to work with each other's intermediate results.