Crate s5_fs_v2 

s5_fs_v2: Unified Node filesystem for S5 (V2)

This crate defines the unified Node architecture for FS5, where everything — files, directories, chunks, and tree nodes — is represented by a single unified Node type stored in CBOR format.

Architecture

• Data model (node): Node, NodeEntry, TraversalContext (on-wire CBOR types)
• Crypto helpers (context): Stateless encrypt/decrypt/compress/decompress functions
• Layer trait (layer): ReadableLayer — async read interface for snapshots and overlays
• Snapshot (snapshot): The main runtime type — immutable prolly tree with node loading, context derivation, file import/export, and recursive walk
• Overlay (overlay): WritableOverlay — mutable layer on top of snapshots
• Merge (merge): MergedView — k-way priority merge over layers
• Persist (persist): Snapshot::merge_and_persist() — diff-aware prolly tree builder with dedup

Modules

chunking

Content-defined chunking for FS5 leaf blobs.

copy

D21 copy — the one new FS5 mechanism that all sharing composes from.

import_stats

Process-wide import-path instrumentation (DIAGNOSTIC, 2026-06-17 s5).

layer

Async read interface for FS5 tree layers.

merge

K-way priority merge over an ordered stack of ReadableLayers.

node

Pure data structures and on-disk (CBOR) schema for FS5 directories.

overlay

Mutable overlay layer for FS5 trees.

persist

Diff-aware persist: merge changes into a prolly tree with deduplication.

pipeline

Per-blob and tree-traversal pipeline operations, factored out of Snapshot so consumers can use them without holding a snapshot.

snapshot

Immutable prolly tree snapshot — the main runtime type for FS5 V2.