I am looking for MongoDB API compatible DB engine that does not require a full blown mongod process to run (kind of SQLite for Node).

From multiple candidates that persistently store data on a local disk with similar API ended up with two:

• NeDB https://github.com/louischatriot/nedb
• tingodb http://www.tingodb.com/

Problem

• I have worked with neither of them.
• I am also very new to the API of MongoDB, so it is difficult for me to judge about comparability.

Requirements

I need your help/advice on picking only one library that satisfies

• It is stable enough.
• It is fast to handle ~1Mb JSON documents on disk or bigger.
• I want to be able to switch to MongoDB as a data backend in the future or by demand by changing a config file. I don't want to duplicate code.

DB initialization api is different

Now only tingodb claims the API compatibility. Even initialization looks fairly similar.

tingodb

var Db = require('tingodb')().Db, assert = require('assert');

vs

mongodb

var Db = require('mongodb').Db,
    Server = require('mongodb').Server,
    assert = require('assert');

In case of NeDB it looks a bit different because it uses the datastore abstraction:

// Type 1: In-memory only datastore (no need to load the database)
var Datastore = require('nedb')
  , db = new Datastore();

QUESTION

Obliviously initialization is not compatible. But what about CRUD? How difficult it is to adopt it?

Since most of the code I do not want to duplicate will be CRUD operations, I need to know how similar they are, i.e. how agnostic can be my code about the fact which backend I have.

// If doc is a JSON  object to be stored, then

db.insert(doc); // which is a NeDB method which is compatiable

// How about *WriteResult*? does not look like it..

db.insert(doc, function (err, newDoc) {   // Callback is optional
  // newDoc is the newly inserted document, including its _id
  // newDoc has no key called notToBeSaved since its value was undefined
});

I will appreciate your insight in this choice!

---

Also see:

• Lightweight Javascript DB for use in Node.js

• Has anyone used Tungus ? Is it mature?