BSON

@deepkit/bson is a high-performance TS implementation of a parser and serializer for BSON, the MongoDB Binary JSON format. It's the fastest JS BSON parser, even faster than native JSON.parse/stringify.

Deepkit has reimplemented it because it's a high-performance framework and both the official JS (js-bson) and C++ (bson-ext) packages are too slow. How slow? When converting 10k elements in an array, js-bson takes 25ms, bson-ext takes 31ms, whiles JSON.parse takes only 5ms. This makes the official BSON parser 5x slower than native JSON.parse. deepkit/type-bson on the other hand takes only 2ms and is therefore 13x faster.

Benchmark

Parsing BSON buffer that contains an array with 10k objects.

Serializing an array with 10k objects.

"deepkit/bson JIT" means a parser/serializer based on a schema like so:

import {t} from '@deepkit/type';
import {getBSONDecoder} from '@deepkit/bson';

interface Model {
    username: string;
    tags: string[];
    priority: number;
}

const decoder = getBSONDecoder<Model>();
const bson = new Buffer([]);

const document = decoder(bson);

whereas "deepkit/type generic" means schema-less:

import {parseObject, ParserV2, ParserV3} from '@deepkit/bson';
const bson = new Buffer([]);

const object1 = parseObject(new ParserV2(bson));

const object2 = parseObject(new ParserV3(bson));

Differences

There are a couple of differences to the official serializer.

• ObjectId is deserialized as string.
• UUID is deserialized as string.
• BigInt is supported and serialized as long.
• Unlimited size BigInt supported (serialised as binary)
• Long is deserialized as BigInt.