What is Mongalayer?

Mongalayer is an abstraction layer between a MongoDB database and a TypeScript (JavaScript) client. It consist of a server @mongalayer/server package and client @mongalayer/client. The server package is responsible for validating schemas, enforcing access rules, and executing MongoDB operations. The client package is a lightweight HTTP client that communicates with the server.

It was created as a self-hosted replacement after MongoDB Atlas App Services deprecation, specifically its Data Model / Data Access Permissions parts and the ability to query MongoDB collections from a client application as you would in a Node.js environment.

It provides:

• Schema validation using Zod to ensure data integrity
• Role-based access control at the document and field level
• Full type safety from server to client
• A client SDK with a familiar API that mirrors the server-side MongoDB methods

Use case

Mongalayer is designed for basic CRUD applications where access control and data integrity matter more than raw throughput. It is a good fit for admin panels, content management systems, multi-tenant platforms, and similar applications.

Architecture

Mongalayer utilizes the MongoDB Node.js driver to communicate with MongoDB. It does not handle authentication or authorization of incoming HTTP requests — that is your responsibility. Instead, Mongalayer focuses on data access control: once a request reaches Mongalayer, it determines what data the caller can read, create, update, or delete based on the access definitions you configure.

┌─────────────────────────┐       ┌──────────────────────────┐       ┌───────────┐
│  Client App             │ ────> │  API Endpoint            │ ────> │  MongoDB  │
│  (+ @mongalayer/client) │ <──── │  (+ @mongalayer/server)  │ <──── │           │
└─────────────────────────┘       └──────────────────────────┘       └───────────┘

Packages

Mongalayer is published under the @mongalayer scope with two packages:

General requirements

• TypeScript 5+ (recommended)
• Zod 4+

@mongalayer/server

The core server-side library. Initializes the Mongalayer instance, validates schemas, enforces access rules, and executes MongoDB operations.

Requirements

• Node.js 22+
• MongoDB Node.js driver 7+

@mongalayer/client

A lightweight HTTP client SDK that communicates with a Mongalayer server. Works in any JavaScript runtime with fetch.

Requirements

• JavaScript environment supporting fetch