jsondb-sequelize-like – A lightweight JSON-based database with Sequelize-like syntax

⚠️ Note: This project is not affiliated with Sequelize. It’s simply inspired by its syntax and modeling philosophy to make transitions easier.

Documentation availables in docs folder

jsondb-sequelize-like is a minimalist, file-based JSON database engine inspired by Sequelize.
It stores your data in flat .json files, supports typed schemas, append-only logs, validation, and a syntax similar to popular ORMs.
Ideal for embedded systems, CLIs, quick prototyping, or educational use.

🚀 Features

• 💾 Flat-file JSON storage
• 🧠 In-memory cache with periodic snapshot (fast processing in history and cache, slow process of storing trigger periodically)
• ✍️ Append-only sync history for safe writes (concurrency-free)
• 🔍 SQL-like querying: where, like, is, etc.
• 🧱 Schema definition with DataTypes, unique, validation, etc.
• 🎯 Auto-incrementing primary keys
• 🗓️ Auto save createdAt and updatedAt
• ✅ Inspired by Sequelize syntax
• 🔒 No external dependencies

Watch our Sequelize Compatibility file for more information or compatibiliy check.

All syntax should be the same as sequelize v6, so you can refer to their documentation to use this package.

📦 Installation

npm install jsondb-sequelize-like

🛠️ Basic Usage

1. Define a model

import Jdb, { DataTypes } from 'jsondb-sequelize-like';

const db = new Jdb();

const User = db.define('user', {
  email: {
    type: DataTypes.STRING(255),
    unique: true,
    validate: /.*@.*/
  },
  password: {
    type: DataTypes.STRING(255)
  }
});

2. Create records

User.create({
  email: '[email protected]',
  password: '123456'
});

3. Query data

const allUsers = User.findAll(); // returns all users

const filtered = User.findOne({
  where: {
    email: { like: '%@example.com' }
  }
});

4. Validate types and uniqueness

User.create({
  email: 'invalid-email', // fails regex validation
  password: 123456         // fails string type check
});

🧪 Schema options (current support)

• type: required — one of DataTypes
• unique: boolean — ensures uniqueness in the dataset
• validate: validates the input on insert
• allowNull: force a field to have a value
• defaultValue: default value for a field if not specify
• ...

💡 Philosophy

The goal of jsondb-sequelize-like is to offer a zero-dependency, file-based DB that mirrors the experience of Sequelize — so you can:

• prototype fast,
• ship lightweight apps (embedded, CLI, offline tools),
• and switch to Sequelize + Any SQL Database supported by sequelize later without rewriting your models and queries at all.

📁 Data Storage Structure

project/
├── data/
│   ├── table.json          ← snapshot (state)
│   └── history/
│       └── history.txt       ← append-only log

Snapshots are periodically written to disk and logs are replayed if needed.

📄 License

Custom : see LICENSE.md

🙌 Author

Aurélien Vaast – GitHub - trainingdev.fr - npm -