Here’s a list of development, hacking or process related interest groups who meet up around York (that I’m aware of). You may see the same faces at some of these groups, York is small! 😉
Agile Yorkshire (Leeds)
Agile Yorkshire meets on the second Tuesday of each month. Sometimes features coding / tech intros, but mostly focused on Agile processes and sharing experiences.
Twitter: @agileyorkshire
Code & Coffee (Leeds and York)
A spin-off from Agile Yorkshire, Code & Coffee is an early morning wake up call in Leeds and York. For those who don’t like a lie-in! Meets every Wednesday early doors.
York Geek Club
The York Geek Club Meets on the first Thursday of each month at The Habit on Goodramgate, 8pm.
Twitter: @yorkGeekClub
York Code Dojo
The York Code Dojo meets up every month, focusing on pairing up on different topics.
Twitter: @yorkCodeDojo
York Hackspace
York Hackspace meets Wednesday evenings, every week, to hack something, hopefully not someone ;-).
Twitter: @YorkHackSpace
York Game Developers
The York Game Developers group meets up in a beer slipper on the second Thursday of every month.
Any more?
Access violation 
There’s a Leeds coding group called Leeds Sharp too, I don’t know if you want to include it as it’s not in York…
Agile Yorkshire is great!
Leeds Sharp is a good Leeds based group.