> ## Documentation Index
> Fetch the complete documentation index at: https://miles.radixark.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Developer Guide

> Architecture, contribution conventions, debugging, and migration notes.

You're here because you want to change Miles, not just use it. This section is the
short tour for new contributors.

<CardGroup cols={2}>
  <Card title="Contributing" icon="file-pen" href="/docs/developer/contributor-guide">
    PR conventions, code layout, how reviews work.
  </Card>

  <Card title="Debugging" icon="bug" href="/docs/developer/debug">
    Aligning precision, separate train/rollout debugging, common kernel pitfalls.
  </Card>

  <Card title="Migration Guide" icon="code-branch" href="/docs/developer/migration">
    Sync → async loop, breaking flag changes between releases.
  </Card>

  <Card title="Architecture Overview" icon="diagram-project" href="/docs/developer/architecture">
    The 30-minute tour of how Miles is organized internally.
  </Card>

  <Card title="Experimental Features" icon="flask" href="/docs/developer/experimental-features">
    Opt-in backends and features (FSDP, …) that aren't production-ready yet.
  </Card>
</CardGroup>

## TL;DR for first-time contributors

1. Pick something small from `good first issue` on [GitHub](https://github.com/radixark/miles/issues).
2. Run the [Reproducibility recipe](/docs/examples/reproducibility) so you can be sure
   "I changed X and it broke" actually means that.
3. Use `--debug-train-only` or `--debug-rollout-only` to scope your changes.
4. Open a PR. We'll review within \~48h.