McKirdy has signed a three-year deal for an undisclosed fee.

The 25-year-old scored 23 goals in 44 appearances for Swindon last season, and has two in his last two matches.

The switch, announced at 01:20 BST, remains subject to Fifa approval.

"We're delighted that he chose to come here after interest from several different clubs," Hibs boss Lee Johnson said.

"Everyone can see how well he's been performing over the last 12-months or so and he's a player that's coming into the prime years of his career.

"He's someone that shows his pitch personality and has a real desire to keep on improving."

Kukharevych joins from French Ligue 1 side Troyes on a season-long loan deal.

The 21-year-old spent 14 months on loan at OH Leuven in the Belgian top-flight, playing 11 times without scoring.

Johnson described Fish as "a dominant centre-back who is comfortable with the ball at his feet".

He added of Kukharevych: "Mykola is a different profile to the other strikers we have in the building, and we look forward to working with him."

Meanwhile, midfielder Dylan Tait, 20, has left Easter Road for a season-long loan with Arbroath in the Championship.