Yes. We looked at all version control systems (fossil, pijul, jj, git, darc, sapling). None provide what we need:

- target the browser

- supports any file format, not just text files

- understands changes, not just versioning of files

- suited to build web apps on top

- ultimately enable 1000's of artists, designers, lawyers, civil engineers, etc. to collaborate

we are 2 years into the journey. dec 16, we'll release a public preview