Deployment

2 articles

Software Engineering 11 Sep 2026 8 min read

Expand and Contract Database Changes for Safe Deployments

Expand and Contract Database Changes for Safe Deployments A database schema can change in milliseconds while an application fleet takes minutes or hours to converge on a new version. During that interval, old and new application instances may use the same database at the same time. That overlap turns an ordinary schema edit into a compatibility problem. Renaming a column in one migration, for example, can break old instances immediately even when the new application code is correct.

Software Engineering Databases

Cloud Computing 01 Sep 2026 5 min read

Blue-Green Deployments for Safer Zero-Downtime Releases

A blue-green deployment keeps two production-capable application environments. One serves live traffic while the other receives the new release. After validation, traffic is switched to the candidate environment. The pattern can make rollback fast, but it does not automatically make a release safe. Database changes, background jobs, caches, and external side effects can still make an old version incompatible with the new state. The basic release sequence Assume blue is currently live and green will run the new version.

DevOps Deployment