Digger crab

The tide line in Miramar was full of hole wsith balls of dirt flung up around them. I waited and watched, and soon enough a tiny crab popped out of the hole with a ball of sand, which it threw out from the hole. Every time it did that, it rested a while and basked in the sun before popping back into the hole to collect some more sand.

 

Any help with the id will be appreciated. The busy little mite is about a cm in size.

Done