http://www.mail-archive.com/fossil-users@lists.fossil-scm.org/msg01641.html

But after that you usually have two completely disjunct trees (because they both start from different "empty commits". So a simple "fossil merge" fails due to no common ancestor.

Assuming both projects have a clean "namespace", so that a simple "unify all files" would work, a way to do exactly that would really be nice.

I am currently trying to write code to create my own manifest to insert it by hand using test-content-put, followed by a rebuild. I have no idea, if this will even work out. Some more "low level tools" to assist people doing some "non standard stuff" would really be nice. For example tools to setup a manifest, check it, and import it.