Open Arsenal

Every update tells a story.

OpenLedger Provenance System is an append-only, event-sourced knowledge infrastructure designed to record not just what is known, but how that knowledge came to be. Instead of treating data as static records, it models information as a continuously evolving graph of events, where every change, correction, interpretation, and dispute is preserved as part of an auditable historical chain. Nothing is overwritten or erased; instead, understanding is refined through successive, traceable updates that maintain full continuity of provenance.

At its core, the system is built around three tightly coupled layers: events, evidence, and methods. Events represent discrete changes or assertions about a record. Evidence provides the verifiable sources that support those assertions, such as documents, lab results, field observations, or sensor outputs. Methods define how conclusions are derived, including analytical processes, scientific techniques, and computational models. By explicitly separating these layers, OpenLedger ensures that every claim can be traced back to both its supporting data and the process used to interpret it.

The platform uses a cryptographically linked event log to guarantee integrity across time. Each event is chained to the previous one, creating a tamper-evident history that can be replayed or reconstructed at any point. This enables time-based queries such as “what was known at this moment in history?” or “how did this interpretation evolve over time?” The system supports branching interpretations, allowing multiple competing hypotheses to coexist without forcing premature consensus or data loss.

OpenLedger also includes a robust provenance graph engine that connects events, evidence, and methods into a navigable structure. This allows users to explore not just the current state of a record, but the full reasoning pathway behind it. Conflicts, corrections, and disputes are treated as first-class citizens in the system, ensuring that disagreement is preserved as part of the historical record rather than overwritten. Combined with modular architecture and AGPL-3.0+ licensing, OpenLedger is designed to serve as an open, extensible foundation for verifiable knowledge systems across scientific, civic, and institutional domains.

This specification is released under the GNU Affero General Public License v3.0 or later (AGPL-3.0+) and may be used freely with required attribution under Section 7. A Specification Branding License is available for attribution-free deployments, with fees based on usage, scope, and deployment size.