# Introduction

Bull is the legacy version of BullMQ. As it is still heavily used today, it is also maintained for bugs but not for new major features. If you want to use a battle-tested queue library and you do not need a better typescript integration or the latest features you are good to go using this library for years to come.

### Used by

Bull has been a part of the NodeJS ecosystem for a long time and is used by many organizations both in commercial and open-source projects. A few special mentions:

![](/files/XJjD139BbEVkdYlYHBka) ![](/files/VwOswax9vGcfDrCKnBAb) ![](/files/nWWJxMvrZtUDVxkkQjgH) ![](/files/ADBFlFkcU8PXqVnRc0P9)

![](/files/OIf1ZBwufJG3Qlg8GGH4) ![](/files/6zsROjjiTcSXFz5gy0XX)

![](/files/AAA4XHtvFpgtMMhhHVLx) ![](/files/aESiALVIbvn4zwGS5rcy)


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.bullmq.io/bull/introduction.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.