What is an “Event” in the rewildingCities Context?

In your system, an event is any meaningful state change in your urban ecosystem data. It's a signal that something new has happened, which may require other parts of the system to react.

Examples of events:

• NewTreePlanted
• CommunityNarrativeSubmitted
• MaintenanceRecordUpdated
• ParcelLandUseChanged
• NewSatelliteImageryAvailable (e.g., for updating UHI buffers)
• PolicyBoundaryUpdated (e.g., a new EJ_zone is designated)
• CitizenScientistPhotoUploaded

An event-driven architecture doesn't have a single, monolithic program. Instead, it has small, independent, specialized services that subscribe to events they care about and do their one job well.

A Proposed Event-Driven Architecture for Your Prototype

Here is a conceptual blueprint for how you could build this in your AWS sandbox. This architecture is designed for modularity, scalability, and directly supports your "recipe-ingredient" model.

1. The Event Ingestion Layer (The Triggers)

This is how events enter your system. You'll have multiple entry points.

• For Batch Data Drops (e.g., City's annual tree census): An S3 Bucket. When a new geojson or parquet file is uploaded, it automatically triggers an event.
• For Real-Time Submissions (e.g., a community member adds a narrative): An API Gateway endpoint that receives the data and passes it to a Lambda function.
• For Scheduled Tasks (e.g., check for new satellite data every day): Amazon EventBridge (Scheduler).

2. The Central Nervous System: Amazon EventBridge (Event Bus)