The 23-year-old Maybury completed his medical on Friday and signed a deal with The Jambos until the summer of 2005 for a nominal fee.
Despite the club`s well-publicised financial problems, the sale of several players seems to have loosened the purse strings just enough to grab the bargain buy of Maybury, who has been unlucky not to figure for Leeds.
The Dublin-born right back has not been a favourite with David O'Leary despite putting in a good performance in Leeds' Champions League clash with Lazio last season.
Hearts boss Craig Levein was delighted to have bought a player with as much class and experience as Maybury, and he will go straight into the team for the SPL clash with St Johnstone on Saturday.
"It's a position I've been looking to fill for ages," said Levein. "Peter Houston and I have watched Alan on about six occasions, albeit mostly for the reserves, and we have always left impressed.
"Never in a million years did I think we would get him. When I found out he was available I was impressed to say the least.
"Alan has been at Elland Road for six years but it's been difficult for him to break into the first team with Danny Mills and Gary Kelly there.
"He is a player who has been capped twice and I think he will do a right good job.
"It's a good signing and I'm grateful to the board for providing the money to sign him when things are tight.
"Despite what some people think, it's not all doom and gloom at Tynecastle."
The gloom could be lifted further should Jamaican international striker Ricardo Fuller impress during his week's trial in Edinburgh.
Fuller has had an unsuccessful spell at Crystal Palace, along with a trial with West Brom and is now looking to Scotland to kick start his career in Britain.
He did manage to get on the scoresheet several times for The Baggies and Hearts would love to bolster their strikeforce, especially as he would not cost them a penny.
