> For the complete documentation index, see [llms.txt](https://docs.nxcframework.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nxcframework.net/nexus-core-docs/reference/compatibility-sets.md).

# Compatibility sets

Which versions belong together.

Nexus Core is several resources that depend on each other's contracts. A **compatibility set** names one version of each that were built, tested, and released together.

**Install a whole set.** Mixing versions from different sets is unsupported, and the failures are confusing rather than obvious — the usual symptom is two resources disagreeing in the log, one tick apart, with neither saying why.

## Where to find them

The current set and every previous one live in the governance repository under `releases/`. Each is a single file naming the versions, what was verified, and — more usefully — what was not.

## Verification levels

| Level         | Means                                                                    | Safe for             |
| ------------- | ------------------------------------------------------------------------ | -------------------- |
| `candidate`   | Tests pass. Deployed to a development server. Never exercised by players | Trying it out        |
| `development` | The above, plus the phase's checks passed on a real server               | A development server |
| `production`  | The above, on a staging environment separate from development            | Nothing yet          |

**No set has ever reached `production`,** and none can until a staging environment exists. A set at `development` has been run by the people who built it and nobody else.

## Reading one

Every set says what it has NOT verified. That section is the useful one — it is where the next failure is, and it is written before anyone finds out rather than after.

## Superseded sets

A superseded set records what was released and what was proven at the time. It is not promoted later, even if the code turned out to be fine: the levels describe an observation, not a judgement.


---

# 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://docs.nxcframework.net/nexus-core-docs/reference/compatibility-sets.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.