# File Conventions

Neutron uses a file-system based router. The files you create in `src/routes` directly determine the routes in your application.

## Basic Mapping

| File Path | URL Path |
| :--- | :--- |
| `src/routes/index.tsx` | `/` |
| `src/routes/about.tsx` | `/about` |
| `src/routes/blog/index.tsx` | `/blog` |
| `src/routes/blog/post.tsx` | `/blog/post` |

## Special Files

-   **`index.tsx`**: The default route for a directory.
-   **`_layout.tsx`**: A layout component that wraps all child routes in its directory.
-   **`_error.tsx`**: An error boundary component that catches errors from child routes.
-   **`_*.tsx`** (any other file starting with `_`): Private files. These are ignored by the router. Use them for co-located components, utilities, or styles.

## Dynamic Routes

You can create dynamic route segments by wrapping the filename in brackets `[]`.

| File Path | URL Path | Params |
| :--- | :--- | :--- |
| `src/routes/users/[id].tsx` | `/users/123` | `{ id: "123" }` |
| `src/routes/posts/[slug].tsx` | `/posts/hello-world` | `{ slug: "hello-world" }` |

## Catch-all Routes

To match all remaining path segments, use the rest syntax `[...]`.

| File Path | URL Path | Params |
| :--- | :--- | :--- |
| `src/routes/docs/[...slug].tsx` | `/docs/guides/setup` | `{ slug: "guides/setup" }` |
| `src/routes/[...404].tsx` | `/any/unmatched/path` | `{ 404: "any/unmatched/path" }` |

## Escaping

If you need a route to actually include brackets in the URL, you likely need to rethink your URL structure, as this is reserved syntax.