Life After Code / Release rehearsals SYNTHETIC CLOUD REPLAY
Live synthetic demo on Google Cloud. Source c222204988f90982f9da0f886ba399d7c521cce3. The video and recorded native GitLab proof use preserved candidate 26550c8.
PERSISTENCE COMPATIBILITY

Ship changes.
Keep the way back.

Rehearse what your previous app reads after a new version writes.
Then read it again through the new version.

THE QUESTION

Can both versions preserve
the last acknowledged value?

old → new → old → new
EXECUTABLE BENCHMARKRun the supplied synthetic fixtures here. Recorded native GitLab proof is linked in the public repository.View readiness →
REHEARSALS IN THIS SESSION00Real database executions
PROTECTED CONTRACT CHECKS16 / 18Base / additive schema fixture
LATEST BUSINESS RESULT—Start a rehearsal to measure
NATIVE RELEASE AUTHORITYPendingSeparate release workflow
THE ROUND TRIP

Healthy isn’t the same as compatible.

PostgreSQL JSONB
01

Old version

Create an order with
street.

ESTABLISH BASELINE
02

New version

Read, create & update
the same stored data.

EXERCISE NEW WRITES
03

Roll back

Read the new records.
Edit through the old app.

PROVE RECOVERY
04

Forward again

Read the old app’s edit.
Catch a stale alias.

VERIFY LAST WRITE
ORIGINAL DEFECT

One key changes.
Rollback breaks.

The candidate writes street_address. The old reader still expects street.

PLAUSIBLE REPAIR

Dual writes.
A stale read remains.

Both keys are written, but a new reader prefers the alias left behind by an old edit.

COMPATIBILITY CONTROL

Preserve the
canonical value.

A supplied fixture keeps the legacy key authoritative. This is not an agent-generated repair.

ADDITIVE SCHEMA CONTROL

Keep the evolved schema.

18 protected checks

Add an unused nullable column and a nonunique index after the old version writes. Return to old code, retain its edits, and verify the evolved schema before moving forward again.

Supplied synthetic control · No arbitrary SQL or native release action

EXECUTION HISTORY

Every result has a record.

THIS PRIVATE SESSION

No rehearsals yet

Choose a scenario above. Results appear only after actual execution.