KurrentDB Development Skill

Provides working code for KurrentDB (formerly EventStoreDB) - the event-native database.

When to Read Additional Files

| Need | Read | |------|------| | Full API reference for any language | reference.md | | Ready-to-run project templates | templates/{language}/ |

Quick Reference

Docker Setup (Insecure Single Node)

docker run --name kurrentdb-node -it -p 2113:2113 \
    docker.kurrent.io/kurrent-latest/kurrentdb:latest \
    --insecure --run-projections=All --enable-atom-pub-over-http

Or use docker-compose - see templates/docker-compose.yaml

Connection String: kurrentdb://localhost:2113?tls=false Web UI: http://localhost:2113

Client Installation Quick Reference

| Language | Install Command | |----------|-----------------| | .NET/C# | dotnet add package KurrentDB.Client | | F# | dotnet add package KurrentDB.Client | | Java | Add com.eventstore:db-client-java:5.3.2 to pom.xml | | Python | pip install kurrentdbclient | | Node.js | npm install @kurrent/kurrentdb-client | | Go | go get github.com/kurrent-io/KurrentDB-Client-Go/kurrentdb | | Rust | Add kurrentdb = "1.0" to Cargo.toml |

Key API Patterns

Optimistic Concurrency (CRITICAL)

ALWAYS use expected revision for aggregates:

• NO_STREAM - Creating new aggregate (stream must not exist)
• StreamExists - Appending to existing stream
• Specific revision number - Prevent concurrent modifications

Subscriptions

• Catch-up: Read history + live events. Use for projections.
• Persistent: Server-managed with ACK/NACK. Use for reliable processing.

System Streams

• $ce-{category} - All events from streams matching pattern (e.g., $ce-order for order-*)
• $et-{eventType} - All events of a type (e.g., $et-OrderCreated)

Official Documentation

• https://docs.kurrent.io/server/
• https://docs.kurrent.io/clients/