QA-208: Add projection migration compatibility tests

[kike-alt]

ID: QA-208
Track: QA
Difficulty: intermediate
Priority: P1
Points: 200

Description

Projection versioning work should ship with compatibility tests so rebuilds and partial upgrades are contributor-safe.

Acceptance Criteria

• Add tests for forward or backward projection compatibility where version metadata changes.
• Cover at least one successful migration path and one intentionally rejected mismatch.
• Add or update tests, fixtures, and docs for the changed surface as needed.

Tech Stack / Files

• backend/src/indexer/projections
• backend/test

Blocked By

#212

Validation Requirements

targeted test suite passes, fixtures are committed, and no maintained CI surface regresses

[karagozemin]

@karagozemin has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I’d like to work on this. Projection compatibility tests are important because indexer rebuilds and partial upgrades should fail safely instead of silently producing bad state.

I can add coverage for version metadata changes, include one valid migration path and one rejected mismatch case, update fixtures/docs where needed, and verify the targeted backend tests pass.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @karagozemin to this issue.

[emrekayat]

@emrekayat has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I’d like to take this on. Migration compatibility is a good QA target because it protects contributors from breaking projection rebuilds during versioned changes.

I can add focused tests around projection version handling, commit the required fixtures, document the expected compatibility behavior, and make sure the maintained CI surface stays clean.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @emrekayat to this issue.

[A6dulmalik]

@A6dulmalik has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi
I’d love to work on this task and contribute a solution for it.
I’ll review the requirements carefully and submit an implementation/update as soon as possible.
Thank you

ℹ️ Repo Maintainers: To accept this application, review their application or assign @A6dulmalik to this issue.

[drips-wave]

Congratulations, @A6dulmalik! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @A6dulmalik: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊