Chances are, you're a Shawn Mendes fan: you know, him of the chart-topping hits Treat You Better, Stitches, Mercy... 

(Yes, you've almost certainly got one of those tunes stuck in your head now. #SorryNotSorry)

So when he offered to perform at the wedding of his friends, Matt and Catherine, they naturally jumped at the opportunity.

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The crooner wrote a song just for the occasion - which took place earlier this month - telling the bride before he began his performance: "Matt and I both wrote this for you, Catherine, so I hope you love it".

And happily enough for those of us who weren't there, a video of the performance was shared by 618 Studios, the videographers the newlyweds hired to film their big day.

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The film was captioned: "Everything about @tmmattjr & @rabbitfoodformybunnyteeth's wedding was special, but their first dance may have been the best ever. So grateful to have captured this moment for them... A custom song performed by their friend @shawnmendes!"

Watch it below (and prepare to want Shawn Mendes to perform at your wedding, too).

Image: Instagram/rabbitfoodformybunnyteeth