City signed the teenager from Wycombe in January but he didn't get any first team action as the Bluebirds lost out in the play offs.
Harris along with the rest of the squad return this week for pre season training with the first duties going to be the team training camp in Switzerland starting next weekend.
“The gaffer shows a lot of confidence and trust in young players,” says Harris.
“I want to break into the starting line-up and make my mark. I am confident, but not arrogant.”
Malky Macky is keen to get Harris involved after being unable to get him a debut in the last campaign.
“We wanted to give Kadeem his debut and if the circumstances had been different he would have played,” says Mackay."I want to set him running in the Championship and he will be given his chance.
“Kadeem has the right attitude and the ability needed to succeed. He is a good person and has the character to learn and progress.
“He came to Cardiff with a zest for training, smiles every day and is desperate to improve his game.
“His chance will come and I believe Kadeem will be an extremely good player for this club over the next few years.”