Rabiega, who signed for Leipzig for £85,000 back in 2013, has been on trial with the Bantams during pre-season, scoring twice in their 2-2 draw with Bradford Park Avenue.
Before that, he had impressed in the early stages of City's first summer fixture with another local non-league outfit, Guiseley, too. However, a calf strain after a lack of playing saw him withdrawn early on, which was a big blow for the lively striker.
The injury meant he missed Bradford's pre-season tour of Scotland, but he has made amends for that and impressed manager Stuart McCall enough to earn a deal.
One for the future
Despite Rabiega's arrival, City's search for a new striker will go on, with McCall seeing the Poland youth international as one for the future.
"We feel he has something we could work with," the manager told Bradford's official website, and now the striker will look to justify that claim by continuing to impress over the season to earn a deal that goes beyond next summer.
"He is a young player and someone who we feel we can develop and progress over time," McCall continued, before confirming that, despite Rabiega being City's 10th signing of the window, they are still in the market for a "more experienced" striker.
City's squad is far from complete, with new additions needed and plenty of players injured, still to return for selection.
This could be Rabiega's chance to stake a claim for place in the team then. First year professional Danny Devine has already benefited from a thin squad, the 18-year-old midfielder nailing down a spot in the starting XI, and his new German teammate will be keen to follow in those footsteps.
However, he does have his work cut out for him as he joins an attacking department that - like few other areas in the team - is well stocked.
Rabiega was on the bench tonight as the Bantams defeated Milton Keynes Dons 2-1, and watched on as Billy Clarke netted the second goal. The Irish striker was probably his easiest target to remove from the starting line-up, given his slow start to the season, but that goal will change a lot.
The team's other strikers include non-league prospect turned club legend James Hanson, who was injured for tonight's game, on-loan Huddersfield Town man Jordy Hiwula and exciting youngster Reece Webb-Foster.
McCall believes that Rabiega "could give [City] an extra option" if they need it, but it seems that his role for now will involve more learning from those around him, than playing regular first team football with them.