The Liverpool keeper, who trained with Alisson Becker, provides competition for goalkeeper Sam Slocombe.
Ian Burchnall said "Vitezslav comes very highly recommended to me by a friend at Liverpool and Michael Doyle has taken a number of very good references from Ireland, so we’re delighted to have him here.
“It’s well documented that we want to get Tiernan Brooks out on loan to further his first-team experience, and as a consequence of that we needed to bring someone else in.
“I didn’t want that person to be a number two who’s comfortable sitting behind Sam Slocombe. Like in every area of the pitch, we want challenge in order to raise the bar.
“Sam was excellent at Wealdstone, has had a good season and is a top professional. He will be driven on by Vitezslav and vice-versa.”