Techniques are provided for providing a type-based message bus with message type hierarchies for non-object oriented languages. In an example, a type-aware message bus receives a subscription message from a subscriber that identifies an object-oriented class. The message bus determines an event channel that corresponds to the class, and subscribes the subscriber to the event channel. The message bus also determines any event channels that correspond to a subclass of the class, and subscribes the subscriber to those event channels. When a publisher publishes a message to an event channel, the message bus publishes the message to each subscriber of the event channel, which can have the effect of publishing the message to subscribers that originally subscribed to superclass event channels of the event channel.