Currently, it is not possible to use other SCM repositories other than GIT on Bitbucket Server. There is an open feature request BAM-18970 to support non-Bitbucket Server repos. Once this is implemented, it should be eventually possible to support other VCS as well (as they will rely on post-commit hook scripts).
Hope that helps.
While Support for non-Bitbucket Server repos for Bamboo Specs (Java and YAML) (BAM-18970) is now available as of Bamboo 6.5, this only includes "Git, Bitbucket Cloud, Github and Subversion repositories", whereas Mercurial didn't make the cut because "according to [Atlassian's] analytics Mercurial repositories usage is really small among [Atlassian's] customers".
Accordingly, please watch and vote for Support Mercurial repository for Bamboo Specs (BAM-19836) to make Atlassian aware of continued interest in Mercurial support.
G’day Community! As we gear up to introduce Bamboo Data Center to the world, we wanted to make sure that we shared a bit more about Bamboo, the product. Our team has put together an overview video ...
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