Git 3.0 will introduce some breaking changes and OneDev code probably need to account for it.

https://git-scm.com/docs/BreakingChanges

Most noteably:

• Commits will change from SHA-1 to SHA256, possibly affecting custom scripts and OneDev database columns holding commit hashes
• Storage will change from files to reftable format, possibly affecting custom OneDev code to access git data on disk

Both can be tested today using git init --object-format=sha256 and git init --ref-format=reftable using latest git.