Former Grimsby Town defender Steven Watt has joined Dover after training at the club since July.
Dover boss Martin Hayes told BBC Kent: "Steve has been training with us on and off for the past three or four weeks. I'm pleased that he's agreed to stay.
"He's turned down a couple of offers to move back up north again."
Full-back Watt, 26, joined Grimsby Town in August and made 27 appearances, scoring twice, but was released at the end of the season.
He began as a youth player at Aberdeen before moving to Chelsea in 2002.
He made just two appearances for the Blues before moving to Swansea but injury cut short his time at the Liberty Stadium so he returned to Scotland.
Hayes added: "It's nice to have someone with that age and experience on board and that will help us with our push to challenge for that top spot this year."