Indeed - what is #EPSO?
It stands for European Personnel Selection Office, and it's the service that handles the competitions for new aspiring staff.
Essentially, if you want to become a civil servant at the EU, you have to pass one of their exams, we just call them EPSOs.
There used to be one for "generalists" every year, but it's been a while.
More info here: https://eu-careers.europa.eu/en/graduates-administrators-ad5