Introduction to Event Sourcing
Event Sourcing in 4 minutes
Learn the big picture and fundamentals of event sourcing in this short video
Why Developers are Adopting Event Sourcing
Challenges of Business Application Development
Monolithic Application and Shared Data Models
- Monolithic applications often force business logic to use shared data models
- If any business logic or model changes, everything has to change
- This dependency makes it challenging to scale and decouple the monolith
Context Loss in Operational Databases
- Operational databases often only keep the current version of each record to maximize performance and minimize storage costs
- This approach overwrites historical snapshots, erasing previous states with every update and delete
- As a result, valuable historical context is lost, making it difficult to support advanced AI and analytics
Event Sourcing 101
Append domain events to the event store
Every change in the application is captured as a domain event and appended to an event store.
Replay events with a projection
Another application can replay these events from the event store using a projection.
Build a custom data model
The projection builds a custom data model optimized for a specific use case, in any database or schema.
Domain Event
A business event representing a change in the application, modeled in language familiar to business stakeholders rather than technical details.
Learn moreEvent Store
An append-only database that records every event in sequence, preserving a complete and permanent log of changes. KurrentDB is an example of an event store.
Learn moreProjection
A function that constructs a data model by sequentially replaying events from the event store.
Decouple Monolithic Applications with Event Sourcing
Separate Data Model from your Business Logic
Domain events are not strongly tied to any specific data model, database, or schema, which helps separate the business logic from the data model.
Modularize Monolithic Application to Services
Monolithic applications can be decoupled into independent vertical slices for microservices or modular monoliths that are easier to evolve, scale, and maintain.
Build Rich, Auditable, and Contextual AI with Event Sourcing
Time Travel and Analyze your Business with a Full Audit Log
Total
Prompt for Insightful Questions only Possible with Historical Events
Which products are most frequently removed from carts?
How often are items swapped for cheaper alternatives?
What accessories are removed when a primary product is removed?
At what cart value do users begin to remove items?
Which items are most commonly added to the cart first?
What sequence of actions leads to cart abandonment?
How does adding a high-value item influence subsequent additions?
Which items are most often added back after being removed?
Do users remove items after viewing shipping costs?
What product combinations are most frequently tried but not purchased?
The world's leading event store for event-sourced applications
Decade of Event Sourcing Expertise
Represents over a decade of refined event sourcing expertise and best practices from thousands of customers.
Immutable Append-Only Log
Features a durable, sequential, and append-only log of immutable events.
Learn moreEvent Indexing
Stores billions of events with indexes to retrieve specific events quickly.
Learn moreNative Pub/sub
Supports Native pub/sub to synchronize other systems in real-time or on-demand.
Programming Platforms
Supports clients for major programming platforms such as .NET, Java, Node.js, Python, Go, and Rust.
Learn moreKurrent Cloud
Offers diverse deployment options, including Kurrent Cloud as a fully managed solution.
Learn more