[feat] revert to a checkpoint

[kubeden]

Problem to solve

It could be nice to be able to revert to a previous commit.

[aritradevelops]

Hi @kubeden I would like to work on this issue, can you please assign me?

[kubeden]

Sure. But let's first wait for #18 to get resolved so we can start working on the updated, easier-to-read codebase.