# Rivox Caching Architecture
Rivox implements a Subtree Content-Addressed Storage (CAS) engine.
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## Key Principles
1. **Subtree Key Derivation (RFC-001)**: Hashing depends strictly on package identity and transitive dependency Merkle roots.
2. **Directory Merkle Manifests (RFC-002)**: Reconstitutes multi-file directory build outputs via 2-level fanout file blobs (`~/.rivox/cache/cas/blobs/ab/cd/hash`) and manifest trees (`TreeManifest`).
3. **REAPI v2 Compatibility**: Implements `build.bazel.remote.execution.v2` wire client protocols for remote caching.