As first reported on this website here, Bastos is a former player of both US Rumelange and SV Eintracht Trier 05, who made his international debut against Russia in 2013, and has made three further appearances for the national team.
Manager Freedman said:
"He's a very young player, 20 years of age, and he is really for the development squad," he said.
"He is studying over there but he's not really for the first team right now. We'll see how things go.
"I keep an eye on the future of this football club. People keep telling me to concentrate on the first team but that's what I do."
Bastos has agreed personal terms and signed an 18-month contract.
It is expected that he will go straight into the Development Squad, where his progress will be closely monitored.