> For the complete documentation index, see [llms.txt](https://note.levelcode.org/software-engineering-notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://note.levelcode.org/software-engineering-notes/readme/3-business-domain.md).

# Business Domain

In DDD, we focus on the **business domain**. Logic involving the business will be prioritized as the focus, which might need a lot of discussion with domain experts.

For example, if you're building a banking system, the business logic is about how to calculate savings and loans interest. As software engineers, while we might know a thing or two about savings and loans, it is more appropriate to have domain experts in this case, bankers, to help us build the system. It is quite important to be in the same table as domain experts and make a **model** (representation of the business domain) based on the discussion.

The technology behind the system such as programming languages, frameworks, or libraries is not the focus here.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## 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, and the optional `goal` query parameter:

```
GET https://note.levelcode.org/software-engineering-notes/readme/3-business-domain.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.