Dating, when do you mention your baggage?

Say you start chatting with someone in a grocery line, and later bump into them at a coffee shop. This leads to a couple dates.
Your interested but you really don’t know the person that well and same the other side.

You have been casually evading anything that comes off as baggage. Keeping things light and fun. But when does it become misleading not to mention baggage that could potentially affect the relationship.