The map type in Go doesn't support concurrent reads and writes. concurrent-map provides a high-performance solution to this by sharding the map with minimal time spent waiting for locks. Prior to Go 1.9, there was no concurrent map implementation in the stdlib. In Go 1.9, sync.Map was introduced. The new sync.Map has a few key differences from this map. The stdlib sync.Map is designed for append-only scenarios. So if you want to use the map for something more like in-memory db, you might...