Retour
The 26-year-old had been without a club since leaving Wigan Athletic by mutual consent in September.
Darcy came through the ranks at Bolton Wanderers and made 35 appearances before heading to Swindon Town.
He also had a spell at Crawley Town and was part of the squad that won the League Two play-offs in 2024.
The midfielder moved to Wigan in January 2025 and went on to make 14 first team appearances for the Latics. He had a spell on loan at Chesterfield before returning to Crawley during the second half of last season.
"I have been on trial for a few weeks, it's been really good, and the lads have been unbelievable with me,” Darcy told the club site.
"It's a situation I have never been in before, being on trial and not having games at weekends, so to finally be back in that environment, I am eager to be back out there. It's a good feeling to sign a contract and I just want to kick on now.
"I have got a few promotions under my belt, I am attack-minded, and I will work hard. I am at my best when I am playing week in, week out."
Manager John Doolan added: "Ronan is a very good player. We have liked what we have seen, we have a few injuries, and we are thankful that the board has backed us on getting him in.
"He has already added to the quality in training, he has shown us a lot already, so it's now up to him to do it on the pitch.
"He has been in the building a while, he knows how it works, he has been involved in shapes, he knows the players, and it should be seamless. He has a lot to offer, he has experience of the league, and has fitted in well."