Build the safeguards
Eight explained steps, a source example and a checkpoint at each decision.
Read the tutorialDelivery / Database migrations / Infrastructure as code
Choose a pattern by the failure it addresses. Several safeguards can be necessary at once.
| Approach | Useful when | Decision or limitation |
|---|---|---|
| Destructive rename | An offline change with all consumers coordinated | Breaks old code during a mixed-version release |
| Expand and contract | Gradual migration with multiple consumers | Requires a compatibility window and retirement evidence |
| Canary rollout | Expose a small portion of traffic first | Needs meaningful signals and a stop condition |
| Application rollback | Restore an earlier compatible application | Cannot automatically restore a deleted schema or data |
| Infrastructure plan | Review declared state changes | Does not execute user workflows |
| Forward repair | Correct a change when rollback is unsafe | Needs a rehearsed operational decision and recovery data |
| Environment | What you can do | Scope |
|---|---|---|
| This browser lab | Click, compare, reset and inspect exact source | Actual PostgreSQL executes the migration and client reads. Traffic and readiness phases are an explicit browser model. The download includes a real loopback HTTP switch and a local-only Terraform plan exercise; no cloud deployment is started from this page. |
| Independent download | Run the same prebuilt lab with Python’s local server | No package installation or automatic external calls needed for the prebuilt preview |
| Native exercise | Run language tests and the included local adapter or script | Requires the documented local toolchain; does not provision a cloud service |
All safeguarded data reads return 200 across mixed versions and application rollback. The destructive path produces missing-column errors. The contract gate refuses to remove a column while an old reader remains.
Begin with an observable outcome, inspect the decisions that produced it, then test a repair. The companion tutorial explains the mechanism; the how-to guide takes the same source into an independent environment.
Verantos emphasizes incremental infrastructure changes, trusted CI/CD and explicit validation and rollback plans.
Eight explained steps, a source example and a checkpoint at each decision.
Read the tutorialUnderstand where each pattern helps and which tradeoffs remain.
Compare approachesDownload the independent environment, run the native checks and try a specific extension.
Open the how-to guide