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Changes

A Change is the atomic, versioned, self-contained unit of change in Flamingock. It encapsulates logic to evolve target systems safely, deterministically, and with complete auditability.

Key characteristics​

  • Atomic execution: Each Change runs exactly once
  • Ordered sequence: Executed based on their order property
  • Auditable: Recorded in the audit store to prevent duplicate execution
  • Safe by default: If Flamingock is uncertain about a change's outcome, it stops and requires manual intervention
  • Rollback capable: Can be undone through rollback methods

What Changes can do​

Changes enable you to version and track changes across your entire technology stack:

  • Message queue operations: Topic creation, schema registry updates
  • Object storage: Bucket setup, file migrations, policy updates
  • Database migrations: Schema changes, data transformations, index creation
  • External API integrations: Service configurations, webhook setups
  • Infrastructure changes: Feature flag updates, configuration changes

Types of Changes​

Written in Java, Kotlin, or Groovy with annotations. Best for complex logic or when you need full programmatic control.

@TargetSystem("user-database")
@Change(id = "add-user-status", author = "dev-team")
public class _0001__AddUserStatus {
    
    @Apply
    public void apply(MongoDatabase database) {
        // Your change logic here
    }
    
    @Rollback
    public void rollback(MongoDatabase database) {
        // Your rollback logic here
    }
}

Safety and recovery​

While Change executions typically complete successfully, Flamingock provides configurable recovery strategies to handle any exceptional circumstances that may arise. If results are uncertain, Flamingock stops and requires manual intervention rather than risking data corruption, ensuring you always know the exact state of your systems.

You can configure different recovery strategies based on your requirements. For complete details on failure handling and recovery workflows, see Safety and Recovery.

Next steps​

Dive deeper into specific aspects of Changes:

Or continue to other key concepts: