&gt; Since a concurrent map (aka. Dictionary aka. Hashtable) is a lot more complex and slow than a non concurrent one, it&#x27;s very very unlikely that Go would ship with its standard map type being a concurrent one. It would be a huge waste.<p>We should develop a system where maps are unsynchronised by default, but when you access them from a second thread they are then converted transparently by the runtime to a thread-safe implementation.