Several years ago I bought a product that aimed to solve this problem. It was a set of rails, a door, and a controller/motor that would raise and lower the door, via a string.

The door itself has a spring loaded catch at the bottom, which is retracted when the door is lifted, via a little mechanism built into the door. Pull up on the peg, the latch retracts, and you can slide the door open

The controller was the weakest part of this whole assembly. It worked, but was crude and often would lock hens out, like when summer thunderstorms would darken the sky. It just used a light sensor

Last year I replaced the controller with an Esphome device I built, and it's been going strong all summer and winter

https://pdx.su/blog/2025-06-11-how-a-simple-chicken-coop-doo...