.net - Domain Model with Event Sourcing -

silly question...but why need domain model @ if use event sourcing.

i have (an event bus of course) and

• application services business operations each send command after basic validation
• command handlers receive commands perform additional command validation , publish events
• event handlers handle events, update read model, , store event in repository (the event source)
• read model services provide read models
• front ends (ui or otherwise) consume read models read model services)...and utilize application services business operations.

why need aggregate roots , domain entities @ all? what's function of additional layer?

sounds may doing bit in command handler. clear - role of command handler receive command, load appropriate aggregate , send command aggregate. grabs events aggregate may have generated persists them , publishes them. here diagram have on blog.

for fuller step step overview of typical cqrs + es application have @ post: cqrs + event sourcing - step step overview

i hope clears things you. ps. may want take @ how create aggregate root cqrs , es. can find post here