EventNotated

EventNotated is a formal schema and associated ecosystem designed to encode, annotate, and exchange events across heterogeneous information systems. It provides a canonical representation for an event, including its identity, timing, type, source, and a structured set of metadata, to enable interoperability, auditability, and reproducibility of event-driven processes.

At its core, an EventNotated record consists of several layers: a unique identifier, a timestamp with time zone, a type or class that describes the event, a source or origin, and a collection of attributes that describe event-specific data. Provisions for provenance tracking, versioning, and relationships (such as causality or containment) are integral to the model. The notation supports extensions through named attribute schemas and can be serialized in multiple formats, commonly JSON-based representations, with optional XML or YAML forms.

Key features include immutability of published events, pluggable validation, and extensible metadata schemas. It emphasizes explicit provenance and lineage, enabling traceability across systems and replays for testing and debugging. EventNotated also defines common semantics for time semantics, time zones, and clock synchronization to reduce ambiguity in distributed deployments.

Organizations use EventNotated to build interoperable event streams for governance, analytics, and automation. It is supported by reference validators, sample datasets, and several SDKs across major programming languages, along with a governance body that maintains the specification and best practices.

Critics note that the formal model can introduce verbosity and learning overhead, but proponents argue that the benefits of consistency, auditability, and cross-system compatibility outweigh the costs. EventNotated remains a developing standard with ongoing extensions to accommodate domain-specific needs.