Bitbucket has feature to see sources at the specified commit: in commit view button "View file", and then navigate anywhere on a source via links at the top. It is VERY NICE feature, but bitbucket has no interface to access it. Button "View file" mean view only that file, and nothing more. Of course, one can navigate there and there via links at the top, but it is looks like a hack.
My suggestion: make in commit view button: "View source on this commit". This button should redirect to
<a href="https://bitbucket.org/Ockonal/the2d/src/403da527444ac0a1e1e7c978b305978cb1045688/?at=master" >View source on this commit</a>
- example of a "commit view":