Crate infinitree

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Infinitree is a versioned, embedded database that uses uniform, encrypted blobs to store data.

Infinitree is based on a set of lockless and locking data structures that you can use in your application as a regular map or list.

Data structures:

Tight control over resources allows you to use it in situations where memory is scarce, and fall back to querying from slower storage.

Additionally, Infinitree is useful for securely storing and sharing any serde serializable application state, or dumping and loading application state changes through commits. This is similar to Git.

In case you’re looking to store large amounts of binary blobs, you can open a BufferedSink, which supports std::io::Write, and store arbitrary byte streams in the tree.


  • Encrypt all on-disk data, and only decrypt on use
  • Transparently handle hot/warm/cold storage tiers; currently S3-compatible backends are supported
  • Versioned data structures allow you to save/load/fork application state safely
  • Thread-safe by default
  • Iterate over random segments of data without loading to memory in full
  • Focus on performance and fine-grained control of memory use
  • Extensible for custom data types, storage backends, and serialization

Example use

use infinitree::{
use serde::{Serialize, Deserialize};

fn main() -> anyhow::Result<()> {
    let mut tree = Infinitree::<VersionedMap<String, usize>>::empty(

    tree.index().insert("sample_size".into(), 1234);

    tree.commit("first measurement! yay!");

Core concepts

Infinitree provides is the first entry point to the library. It creates, saves, and queries various versions of your Index.

There are 2 types of interactions with an infinitree: one that’s happening through an Index, and one that’s directly accessing the object structure.

Any data stored in infinitree objects will receive a ChunkPointer, which must be stored somewhere to retrieve the data. Hence the need for an index.

An index can be any struct that implements the Index trait. There’s also a helpful derive macro that helps you do this. An index will consist of various fields, which act like regular old Rust types, but need to implement a few traits to help serialization.


You can think about your Index as a schema. Or just application state on steroids.

In a more abstract sense, the Index trait and corresponding derive macro represent a view into a single version of your database. Using an Infinitree you can swap between, and mix-and-match data from, various versions of an Index state.


An Index contains serializable fields. These are thread-safe data structures with internal mutation, which support some kind of serialization Strategy.

You can use any type that implements serde::Serialize as a field through the fields::Serialized wrapper type, but there are incremental hash map and list-like types available for you to use to track and only save changes between versions of your data.

Persisting and loading fields is done using an Intent. If you use the Index macro, it will automatically create accessor functions for each field in an index, and return an Intent wrapped strategy.

Intents elide the specific types of the field and allow doing batch operations, e.g. when calling Infinitree::commit using a different strategy for each field in an index.


To tell Infinitree how to serialize a field, you can use different strategies. A Strategy has full control over how a data structure is serialized in the object system.

Every strategy receives an Index transaction, and an object::Reader or object::Writer. It is the responsibility of the strategy to store references so you can load back the data once persisted.

There are 2 strategies in the base library:

  • LocalField: Serialize all data in a single stream.
  • SparseField: Serialize keys and values of a Map in separate streams. Useful for quickly iterating over key indexes when querying. Currently only supports values smaller than 4MB.

Deciding which strategy is best for your use case may mean you have to run some experiments and benchmarks.

See the documentation for the Index macro to see how to use strategies.

Cryptographic design

To read more about how the object system keeps your data safe, please look at file in the main repository.



  • Backends work with underlying persistence layers.
  • Encryption key management and secure hashing
  • Traits and implementations for working with index members.
  • Working with the index of an Infinitree.
  • Tools for working directly with objects, without the indexing system.
  • Main tree and commit management


  • A pointer for a chunk of data in the object system.
  • An incremental hash state that can accept any number of writes.


Derive Macros

  • Example use of the derive macro: