So, with the newly acquired enclosures, the need to get half a dozen locks has arisen. Any suggestions? Any recommendations?

There's not much of a need to keep other people out, I'm mostly concerned with keeping the snakes in (yes, one of my wandering garters managed to partially open a door within 5 minutes of entering the enclosure). I'm also not a fan of having to use a different key for each enclosure, so any solution that prevents the doors from sliding would be great.

I also have a plan to reduce the gap between the doors to an absolute minimum, so it should preferably be a lock or locking mechanism that doesn't need to fit between the doors. Or if it did need to fit between them, it shouldn't need more than a millimeter or two.

I have a couple of ideas for very simple home-made locks myself, but I'd prefer not to have to use them.