Introduction

Welcome to ChronDB! A modern, Git-based database that remembers everything.

What is ChronDB?

ChronDB is a chronological database built on Git's powerful architecture that gives your data complete version history. Think of it as "Git for your database" - every change is tracked, every version is accessible, and you can time-travel through your data's complete history.

ChronDB is licensed under the GNU Affero General Public License v3.0 (AGPLv3), ensuring improvements deployed as hosted services remain available to the community.

Why Choose ChronDB?

• Complete History - Never lose data again. Every change is preserved in your database's timeline.

• Time Travel - Query your data as it existed at any point in time.

• Branching & Merging - Create isolated environments for testing, development, or experimentation.

• Multiple Interfaces - Connect through Clojure, REST API, Redis protocol, or even PostgreSQL protocol.

• ACID Compliance - Enjoy full transaction support with commit, rollback, and consistency guarantees.

• Schema-less - Store any JSON-compatible data without rigid structure requirements.

• Lucene-Powered Search - Execute full-text, composite, and geospatial queries using Lucene's production-grade indexing engine.

How It Works

ChronDB leverages Git's internal structure as a storage engine:

Repository (database)
  └── Branches (schemas/environments)
       └── Directories (tables)
            └── Files (documents as JSON)

Each document is a file in the Git repository, and each change creates a commit in the history. This gives you all the power of Git for your database:

• See diffs between versions

• Browse commit history

• Create branches for development

• Merge changes between branches

• Tag important versions

• Hook into events

Quick Example

Here's how simple it is to use ChronDB with its Clojure API:

;; Create/connect to a database
(def db (chrondb/create-chrondb))

;; Create a user document
(chrondb/save db "user:1" {:name "Alice" :email "[email protected]"})

;; Update the document
(chrondb/save db "user:1" {:name "Alice" :email "[email protected]" :role "admin"})

;; Time travel: see how the document looked yesterday
(def yesterday (chrondb/get-at db "user:1" "2023-07-15T00:00:00Z"))

;; See all versions of the document
(def history (chrondb/history db "user:1"))

Choose Your Interface

ChronDB speaks multiple protocols so you can connect with your favorite tools:

• Native Clojure API - Direct, powerful access from Clojure applications

• REST API - HTTP interface for any language or client

• Redis Protocol - Use Redis clients to connect directly

• PostgreSQL Protocol - Connect with SQL clients and tools

Start Your Journey

New to ChronDB? Here's how to get started:

1. Quick Start Guide - Up and running in minutes

2. Core Concepts - Understand ChronDB's data model

3. Examples - See ChronDB in action

4. API Reference - Complete API documentation

Ready to dive in?

→ Get Started Now

Community Resources

• Official Documentation: chrondb.avelino.run

• Join our Community: Discord

• Discussions & Ideas: GitHub Discussions