# nxdns documentation

The pages are split by what you are trying to do, following
[Diátaxis](https://diataxis.fr/). Each page serves one of four purposes, and
knowing which one you want is the fastest way to the right page.

| Mode | For | Read it when |
| --- | --- | --- |
| [Tutorial](#tutorial) | Someone who has never run nxdns | You want to learn what it does by making it work once |
| [How-to guides](#how-to-guides) | An operator with a job to do | You know what you want and need the steps |
| [Reference](#reference) | Anyone who needs an exact answer | You want a field, a flag, a route or an exit code |
| [Explanation](#explanation) | Anyone deciding or debugging | You want to know why it works the way it does |

## Tutorial

A lesson, not a procedure: one path with one outcome, on a scratch directory you
can delete afterwards.

- [tutorial/first-run.md](tutorial/first-run.md) — build nxdns, resolve a name,
  block a domain from a real blocklist, open the web interface, stop cleanly.

## How-to guides

Steps for a goal you already have. They assume you know what nxdns is.

- [how-to/verify-a-release.md](how-to/verify-a-release.md) — check the
  signature and the checksums before you run anything, and what they prove.
- [how-to/install-with-systemd.md](how-to/install-with-systemd.md) — a real
  install as a system service, including the Raspberry Pi 5 aarch64 binary.
- [how-to/install-with-docker.md](how-to/install-with-docker.md) — the published
  container image and the compose file.
- [how-to/upgrade.md](how-to/upgrade.md) — move to a new release without losing
  state.
- [how-to/troubleshoot.md](how-to/troubleshoot.md) — what to do when it does not
  answer, does not block, or will not start.
- [how-to/enable-doh-and-dot.md](how-to/enable-doh-and-dot.md) — serve encrypted
  DNS with certificates.
- [how-to/set-up-admin-authentication.md](how-to/set-up-admin-authentication.md)
  — put a password on the web interface and the API.
- [how-to/back-up-and-restore.md](how-to/back-up-and-restore.md) — export and
  import the configuration, and what to copy.
- [how-to/measure-performance.md](how-to/measure-performance.md) — run the
  benchmark harness on your own hardware.

## Reference

Descriptions of what is there. No procedures, no advice.

- [reference/configuration.md](reference/configuration.md) — every
  configuration section, field, default and range.
- [reference/api.md](reference/api.md) — every REST route, authentication and
  the event stream.
- [reference/cli.md](reference/cli.md) — the six subcommands, every flag, every
  exit code.
- [reference/files-and-directories.md](reference/files-and-directories.md) — the
  data directory layout and file modes.
- [reference/performance.md](reference/performance.md) — the targets and the
  measured numbers.

## Explanation

Background. Nothing here is needed to operate nxdns; it is here so the decisions
are inspectable.

- [explanation/architecture.md](explanation/architecture.md) — the module map
  and the design it comes from.
- [explanation/configuration-model.md](explanation/configuration-model.md) — why
  the file seeds the database once and the database is the truth afterwards.
- [explanation/performance-and-testing.md](explanation/performance-and-testing.md)
  — why the targets exist, why CI does not gate on them, and what the hermetic
  tests do and do not prove.

Scope and per-milestone contracts live outside this directory, in
[../PLAN.md](../PLAN.md) and [../specs/](../specs/).