Alun Armstrong has wasted no time putting his mark on Darlington's squad since taking over last month.
Hatfield, who started his career at Leeds United and made 163 appearances in a Guiseley shirt over a four-year stint.
Darlington are looking to improve on two mid-table finishes in the last two seasons, something Hatfield wants to make a reality.
"I've got a lot of experience in this league and the one above so hopefully I can bring that to the team," he told the club's video service.
"I'm looking to get out of this league with this club and I'm delighted to be here - we're only looking upwards."
Darlington start their 2019/20 National League North season against Farsley Celtic on August 3 - you can view a full list of fixtures by clicking here.