"I'm really proud of the players' performance under a lot of pressure in front of 74,000 fans," said de Villiers, who saw his side outscore the Grand Slam winners by two tries to nil at the Millennium Stadium.
"It was very important to showcase our talents and we will celebrate this win.
"We saw the passion of the Welsh and they came out all guns blazing but that's what Test rugby is all about. It's tough but we can build on this."
The win sets the Boks up for Tests against Scotland and England over the next two Saturdays and de Villiers feels the togetherness of his team will stand them in good stead for the next fortnight, as well as next summer's Lions tour.
"The way they stood up as a team together when things went down hill - you could easily lose your head under circumstances like that. The team stuck together and stood together as one and that to me is a great thing to build on. We really feel good about that.
"Then again, the Lions is not until next year. A lot of things can happen between now and next year. There can be a lot of injuries, players lose form and these kind of things can happen.
"But we'll take this win, move on and from there, see how it unfolds until the Lions tour."