[ChristopherWirt]

Why

• vortex.listLayout writes the vortex.list layout, in our draft list layout edition.
• Upstream keeps vortex.list in its unstable edition, so it can change the format in any merge.
• The event store writes its files this way, so a silent format change would leave files nothing can read.

What

Golden files in vortex-jni/goldenfiles/list_layout/, written once through the vortex.listLayout write path. They cover primitive, nullable, string, struct and nested list elements, a list inside a struct, and all-empty lists, each 20,000 rows across several blocks.

Every build checks two things:

• Reads: each file still reads back to its values, through full scans, row ranges, row indices, projections, filters, list_contains and list_transform pushdown.
• Writes: today's writer still writes the same list layouts: their metadata, children, dtypes and row counts.

The files are never regenerated by the check. A separate #[ignore]d test only writes missing files, for adding cases. The README explains what to do when a check fails.

Rename the edition to qc2026.11.0

• It was jni2026.11.0, named after the vortex-jni crate. An upstream jni family in that crate would collide with it.
• Edition names aren't stored in files, so files already written, including these golden files, read the same.
• Eventstore records the name, so it must move to this build and qc2026.11.0 together.

Make qc2026.11.0 immutable, freezing in 0.91.0

• Declared immutable: true, with min_library_version still None. Vortex freezes an edition by setting min_library_version to the release that freezes it.
• Set it to "0.91.0" once the fork's first 0.91.0 build is cut. Changes landed after 0.90.0, so "0.90.0" would claim readers that may not read these files.
• The golden files hold the format fixed from now on either way.
• list_layout_edition_becomes_immutable fails if a merge makes it mutable.

Checked

I broke the format three ways, and the tests caught each one:

Change	Failed
Writer stores i64 offsets	7 write checks
Reader swaps the elements and offsets children	all 52
ListLayoutMetadata field renumbered	41

Testing

• cargo test -p vortex-jni --lib: 71 passed.
• cargo clippy -p vortex-jni --all-targets --all-features -- -D warnings: clean.
• cargo +nightly-2026-09-10 fmt -p vortex-jni: applied.

🤖 Generated with Claude Code

[gitRasheed]

lgtm, fyi hours written so far record jni2026.11.0, so its checkReadable will reject them on this build but don't think it matters

[ChristopherWirt]

think we're good - but we should clear out the bucket anyway of all the old files we've let everywhere