If you surprise them with your intentions, they just might surprise you with the door.
A better approach, if you can take the time to go through it, might be to work full-time for a year, and prove your worth many times over to the company. At that point, ask if you can move to working part-time. They'd likely rather keep a good programmer on staff part-time than let you go entirely.
In my experience, part-time programming jobs tend to pop up more frequently at research universities than at corporations. It may follow as well that a university would be more flexible in turning a full-time job into a part-time job, if asked.
A better approach, if you can take the time to go through it, might be to work full-time for a year, and prove your worth many times over to the company. At that point, ask if you can move to working part-time. They'd likely rather keep a good programmer on staff part-time than let you go entirely.
In my experience, part-time programming jobs tend to pop up more frequently at research universities than at corporations. It may follow as well that a university would be more flexible in turning a full-time job into a part-time job, if asked.