Warsaw tips anyone?

Flying to Warsaw in a week for a week of work. Not sure if I will have any free time (or energy to use free time!) but curious if there are any Warsaw don’t miss things?

A stroll along the Vistula or through Lazienki Park is pleasant.
For dining, I enjoyed N31 and Soul Kitchen.
edit: If you have Sundays free: Chopin Concerts in Royal Łazienki Park

Thanks Tom! making a list and starting to get excited about going.