Software → Databases
Expand and Contract Pattern
A backward-compatible migration strategy that adds new structures before removing old ones.
What it is
A backward-compatible migration strategy that adds new structures before removing old ones.
Why it matters
Expand and Contract Pattern helps teams reduce ambiguity, coordinate changes, and manage the risk of moving software from source code to users. Its value depends on clear ownership, automation, and feedback rather than the label alone.
Practical guidance
- Define the policy or workflow explicitly.
- Keep changes small, traceable, and reversible.
- Automate repeatable validation where possible.
- Connect decisions to artifacts, environments, releases, and production evidence.
- Review the practice when it creates delay without improving safety.