CQRS & Event Sourcing
Course Index
28 Lessons · 3 Sections
Master CQRS & Event Sourcing — the architectural patterns enabling audit trails, temporal queries & independent scaling of reads and writes. Covers command handlers, event stores, projections, snapshots & integration with Kafka. Includes 4 production builds: CQRS system, event store, projection engine & full audit system.
28Lessons
3Sections
4Projects
FreeAccess
Section 1CQRS & Event Sourcing FundamentalsLessons 1–10
Lesson 1
What is CQRS? Command Query Separation Origins
Lesson 2
Commands, Queries & the Write/Read Split
Lesson 3
CQRS Without Event Sourcing
Lesson 4
What is Event Sourcing? Events as Source of Truth
Lesson 5
The Event Store: Append-Only Log
Lesson 6
Aggregates in Event Sourcing
Lesson 7
Projections & Read Models
Lesson 8
CQRS + Event Sourcing: The Natural Pairing
Lesson 9
Snapshots: Performance Optimisation
Lesson 10
Event Schema Design & Versioning
Section 2Advanced Patterns & FrameworksLessons 11–22
Lesson 11
Optimistic Concurrency in Event Stores
Lesson 12
Eventual Consistency in CQRS Systems
Lesson 13
Replay: Rebuilding State from Events
Lesson 14
CQRS with MediatR (.NET)
Lesson 15
CQRS with Axon Framework (Java)
Lesson 16
Event Stores: EventStoreDB (Kurrent) & Marten
Lesson 17
CQRS & Event Sourcing with Kafka
Lesson 18
Outbox Pattern in Event-Sourced Systems
Lesson 19
Saga Pattern with CQRS & ES
Lesson 20
Testing CQRS & Event Sourcing Systems
Lesson 21
When NOT to Use CQRS & Event Sourcing
Lesson 22
CQRS & ES in 2026: Maturity & Tooling
Section 3Anti-Patterns, Case Studies & ProjectsLessons 23–28