ProllyTree

A probabilistic B-tree implementation in Rust that combines B-tree efficiency with Merkle tree cryptographic properties. Designed for distributed systems, version control, and verifiable data structures.

Features

• High Performance: O(log n) operations with cache-friendly probabilistic balancing
• Cryptographically Verifiable: Merkle tree properties for data integrity and inclusion proofs
• Multiple Storage Backends: In-memory, File, RocksDB, and Git-backed persistence
• Distributed-Ready: Efficient diff, sync, and three-way merge with pluggable conflict resolvers
• Python Bindings: Full API coverage via PyO3 with async support
• SQL Interface: Query trees with SQL via GlueSQL integration

Quick Start

Add to your Cargo.toml:

[dependencies]
prollytree = "0.3.4-beta"

# Optional features
prollytree = { version = "0.3.4-beta", features = ["git", "sql"] }

Examples

Verifiable key-value store

A ProllyTree is a Merkle tree, so any key-value pair comes with a cryptographic inclusion proof.

use prollytree::tree::{ProllyTree, Tree};
use prollytree::storage::InMemoryNodeStorage;

let mut tree = ProllyTree::new(InMemoryNodeStorage::<32>::new(), Default::default());
tree.insert(b"user:alice".to_vec(), b"Alice".to_vec());

let proof = tree.generate_proof(b"user:alice");
assert!(tree.verify(proof, b"user:alice", Some(b"Alice")));

Git-backed versioning

The git feature stores tree nodes as Git objects, so commits, branches, and merges work natively on key-value state.

use prollytree::git::versioned_store::StoreFactory;

let mut store = StoreFactory::git::<32, _>("data")?;
store.insert(b"config/api_key".to_vec(), b"v1".to_vec())?;
store.commit("Initial config")?;

store.create_branch("experimental")?;
store.insert(b"config/api_key".to_vec(), b"v2".to_vec())?;
store.commit("Try new key")?;
// → diff, merge, history available; see the user guide

See examples/ for SQL queries, additional storage backends, and agent memory patterns.

Feature Flags

Feature	Description	Default
git	Git-backed versioned storage with branching, merging, and history	Yes
sql	SQL query interface via GlueSQL	Yes
rocksdb_storage	RocksDB persistent storage backend	No
python	Python bindings via PyO3	No
tracing	Observability via the tracing crate	No
digest_base64	Base64 encoding for digests	Yes

[dependencies.prollytree]
version = "0.3.4-beta"
features = ["git", "sql", "rocksdb_storage"]

Performance

Benchmarks (Apple M3 Pro, 18GB RAM):

• Insert: ~8-21 us (scales O(log n))
• Lookup: ~1-3 us (sub-linear due to caching)
• Memory: ~100 bytes per key-value pair
• Batch operations: ~25% faster than individual ops

Run benchmarks: cargo bench

Testing

# Rust tests
cargo test --features "git sql"

# Python tests (build bindings first)
./python/build_python.sh --all-features --install
python -m pytest python/tests/

Documentation & Examples

• User Guide & Theory – mkdocs site with the full tour (theory, CLI, Python, examples)
• Rust API Reference – auto-generated from source
• Use Cases & Examples – version control, SQL, proofs, storage backends
• Python Bindings – Python-specific quickstart

CLI Tool

cargo install prollytree --features git
git-prolly --help

See the user guide for a full CLI walkthrough.

Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

License

Licensed under the Apache License 2.0. See LICENSE.