Skip to content
CAI
Produce a survey ↗Verify a survey

johanhaleby/occurrent

This system is an event sourcing framework that manages domain state through immutable events, supporting both traditional stream-based and Dynamic Consistency Boundary (DCB) architectures. It provides comprehensive tooling for command composition, query filtering, and materialized view construction across both blocking and reactive execution models. The codebase includes robust persistence integrations for MongoDB and Redis, alongside a rich set of examples demonstrating various domain patterns.

63.1

Adequate · 20 July 2026

50k

lines of production code

Java

with Kotlin

1

bus factor · 8 authors in all

2

measurements over time

CAI band scale
CAI trend line

How it got here

2020 · DCB support and MongoDB integration

This period focused on introducing Dynamic Consistency Boundary (DCB) support and expanding the MongoDB integration with native, Spring, and Reactor implementations. The team also modernized the codebase by upgrading to Java 21, adopting Jakarta EE, and adding comprehensive test coverage for the new subscription and event store APIs.

70 changes

2021–2024 · Kotlin DSL and CloudEvent integration

This period focused on expanding Kotlin support through new DSLs for deciders, views, and queries, alongside comprehensive CloudEvent conversion and type mapping features. The team also introduced deadline scheduling, refined MongoDB subscription models, and added extensive test coverage across the new modules.

45 changes

2026 · Dynamic Consistency Boundary (DCB) implementation

This period focused on introducing the Dynamic Consistency Boundary (DCB) pattern across the codebase, including new APIs, application services, and DSLs for both blocking and reactive stacks. The work also expanded the example applications to demonstrate DCB capabilities and added comprehensive test coverage for the new features.

62 changes

CAI lens gauges

Survey your own repository

johanhaleby/occurrent was measured the same way every project in this corpus was: the same rubric, at a pinned commit, with the result published in full. Point the surveyor at a repository you know and see whether you agree with it.

Survey a repository

About this page

  • The description of this project is derived from its own commit history, not from its README.
  • The score is its highest published measurement, taken on 20 July 2026 at a pinned commit. It is not a live figure and does not change until the project is measured again.
  • Measured at commit 0d2b9cb30b — the exact code this score is about.
  • Scored under rubric rubric-2026.08.17. Score the same commit under that rubric and you get the same number.
CAI link cards