It is great to know you and your friends are thinking of traveling to Ireland.
The new rules indeed state that even if you are vaccinated, you need to have a negative result from a PCR test taken a maximum of 72 hours before arriving in Ireland or an antigen test taken maximum 48 hours before. This means that when you arrive in Ireland you will need to present your Digital Covid Certificate and the negative test result. You can read more about this new restriction on the Traveler's Health
page and the Ireland Government's
Wishing you safe travels,