Hey all, Following up on the proposal above.
TL;DR: I’m proposing *branch-specific schema evolution* so Iceberg branches can evolve schemas independently instead of sharing a single global schema. This enables: - Safe schema experimentation and migration testing on branches without impacting production - schema changes are isolated and only merged back when semantics are unambiguous To support this, we’d need a spec change: add an optional *schemaId* to *SnapshotRef* to record which schema a branch ref points to. More details can be found in this proposal doc <https://docs.google.com/document/d/1yzE3Mm_ZALdWv_5HlMlGL0sk4-G4zU9oqxdo2ufQi3I/edit?tab=t.0#heading=h.g7zu7nim8ekj> and here is the Draft PR <https://github.com/apache/iceberg/pull/15012> for the high level direction I am going. Looking forward to the feedback, thanks! Best, Yingjian On Mon, 12 Jan 2026 at 15:23, Yingjian Wu <[email protected]> wrote: > Hey all, > > I'd like to start a discussion about supporting schema evolution on > Iceberg branches, as there are some interests and some discussions around > this feature. > > Would appreciate feedback on this proposal doc > <https://docs.google.com/document/d/1yzE3Mm_ZALdWv_5HlMlGL0sk4-G4zU9oqxdo2ufQi3I/edit?tab=t.0#heading=h.g7zu7nim8ekj> > and > here is the Draft PR <https://github.com/apache/iceberg/pull/15012> for > the high level direction I am going. > > Best, > Yingjian >
