React Router Auto Routes

Automatic folder-based routing with colocation for React Router v7+.

Principles

Built on convention-over-configuration principles—your file structure defines your routes automatically, with smart defaults that just work, and scale well.

Colocation is a first-class feature:

> "Place code as close to where it's relevant as possible" — Kent C. Dodds

Keep your components, tests, utilities, and routes together. No more hunting across folders or artificial separation of concerns. The + prefix marks non-route files for cohesive, feature-based code organization.

Features

- 📁 Flexible file organization - Mix and match folder-based and dot-delimited notation
- 🎯 Prefix-based colocation - Keep helpers and components alongside routes using + prefix
- 📦 Monorepo / sub-apps support - Mount routes from different folders to organize multi-app projects
- ⚡ ESM-only - No CommonJS, built for modern tooling
- 🧹 Clean API - Simplified options and intuitive conventions

Quick Start

Install:

``bash
npm install -D react-router-auto-routes
`

> The migration CLI relies on your project's own TypeScript install. Make sure typescript@>=5.0 is already in devDependencies if you plan to run npx migrate-auto-routes.

Use in your app:

`ts
// app/routes.ts
import { autoRoutes } from 'react-router-auto-routes'

export default autoRoutes()
`

> Migrating from remix-flat-routes? See the Migration Guide below.

Routing Convention

Folder-based structure:

`
routes/
├── index.tsx → / (index route)
├── about.tsx → /about
├── robots[.]txt.ts → /robots.txt (literal dot segment)
├── _auth/ → Pathless layout (no /auth in URL)
│ ├── _layout.tsx → Auth layout
│ ├── login.tsx → /login
│ └── signup.tsx → /signup
├── blog/
│ ├── _layout.tsx → Layout for /blog/* routes
│ ├── index.tsx → /blog
│ ├── $slug.tsx → /blog/:slug (dynamic param)
│ └── archive.tsx → /blog/archive
├── dashboard/
│ ├── _layout.tsx → Layout for dashboard routes
│ ├── index.tsx → /dashboard
│ ├── analytics.tsx → /dashboard/analytics
│ └── settings/
│ ├── _layout.tsx → Layout for settings routes
│ ├── index.tsx → /dashboard/settings
│ └── profile.tsx → /dashboard/settings/profile
└── files/
└── $.tsx → /files/* (splat - catch-all)
`

Equivalent flat (dot-delimited) structure:

`
routes/
├── index.tsx → / (index route)
├── about.tsx → /about
├── robots[.]txt.ts → /robots.txt (literal dot segment)
├── _auth._layout.tsx → Auth layout
├── _auth.login.tsx → /login
├── _auth.signup.tsx → /signup
├── blog._layout.tsx → Layout for /blog/* routes
├── blog.index.tsx → /blog
├── blog.$slug.tsx → /blog/:slug (dynamic param)
├── blog.archive.tsx → /blog/archive
├── dashboard._layout.tsx → Layout for dashboard routes
├── dashboard.index.tsx → /dashboard
├── dashboard.analytics.tsx → /dashboard/analytics
├── dashboard.settings._layout.tsx → Layout for settings routes
├── dashboard.settings.index.tsx → /dashboard/settings
├── dashboard.settings.profile.tsx → /dashboard/settings/profile
└── files.$.tsx → /files/* (splat - catch-all)
`

Both structures produce identical routes. Use folders for organization, flat files for simplicity, or mix both approaches as needed.

Route patterns:

- index.tsx or _index.tsx - Index routes (match parent folder's path).
- Index routes automatically nest under layouts with matching path segments—for example, admin/index.tsx nests under admin/_layout.tsx.
- _layout.tsx - Layout with for child routes
- Only layout files create nesting. Non-layout routes that share prefixes stay siblings (e.g., users.$id.tsx and users.$id.edit.tsx).
- Other _ prefixes (like _auth/) create pathless layout groups
- $param - Dynamic segments (e.g., $slug → :slug)
- $.tsx - Splat routes (catch-all)
- (segment) - Optional segments (e.g., (en) → en?)
- ($param) - Optional dynamic params (e.g., ($lang) → :lang?)
- robots[.]txt.ts (and similar) - Escape a literal . (or other special characters) inside [...] to generate file-like routes such as /robots.txt

Key insight: Folders are just a convenience for organization. Without a parent file, api/users.ts behaves exactly like api.users.ts - both create the same /api/users route.

Colocation with + Prefix

Keep helpers, components, and utilities alongside routes using the + prefix. Anything starting with + is ignored by the router.

`
routes/
├── dashboard/
│ ├── index.tsx → Route: /dashboard
│ ├── +/
│ │ ├── helpers.ts
│ │ └── types.tsx
│ └── +components/
│ └── data-table.tsx
└── users/
├── index.tsx → Route: /users
├── +user-list.tsx
└── $id/
├── index.tsx → Route: /users/:id
├── edit.tsx → Route: /users/:id/edit
└── +/
├── query.ts
└── validation.ts
`

Import colocated files using relative paths:

`ts
import { formatDate } from './+/helpers'
`

Rules:

- Allowed: Use + prefixed files and folders anywhere inside route directories (including anonymous +.tsx files and +/ folders)
- Disallowed: Don't place + entries at the routes root level like routes/+helpers.ts (but routes/_top/+helpers.ts is fine)
- Note: +types is reserved for React Router's typegen virtual folders so avoid that name.

Configuration Options

`ts
autoRoutes({
routesDir: 'routes',
ignoredRouteFiles: ['*/.'], // Ignore dotfiles like .gitkeep
paramChar: '$',
colocationChar: '+',
routeRegex: /\.(ts|tsx|js|jsx|md|mdx)$/,
})
`

.DS_Store is always ignored automatically, even when you provide custom ignoredRouteFiles, and the migration CLI inherits the same default.

Note: Prefer using the + colocation prefix over ignoredRouteFiles when possible. Ignored files skip all processing including conflict detection, while colocated files still benefit from validation checks like ensuring proper placement. For example, place tests in +test/ folders rather than using */.test.{ts,tsx} in ignoredRouteFiles.

Directory resolution notes

- routesDir entries stay relative (no absolute paths), but you can point outside the app folder with parent segments like '../pages'. Paths are resolved from the project root (process.cwd()).
- When you mount / to a folder, import prefixes are anchored to that folder’s parent so generated file values stay short (e.g., '/': 'packages/web/routes' keeps routes/ imports instead of ../packages/web/routes/).
- Without a / mount, the app directory defaults to /app; override it by defining globalThis.__reactRouterAppDirectory (React Router’s config can set this) to match custom app roots such as app/router.

$3

routesDir accepts two shapes:

- string – scan a single root. When omitted, the default 'routes' resolves to app/routes so existing folder structures continue to work with zero config.
- Record – mount filesystem folders to URL paths (key = URL path, value = filesystem folder). Folder paths resolve from the project root so you can mount packages that live outside app/.

Mount routes from different folders to organize sub-apps or monorepo packages:

`ts
autoRoutes({
routesDir: {
'/': 'app/routes',
'/api': 'api/routes',
'/docs': 'packages/docs/routes',
'/shop': 'packages/shop/routes',
},
})
`

Example structure:

`
app/
routes/
dashboard.tsx → /dashboard
settings/
_layout.tsx → /settings (layout)
index.tsx → /settings
api/
routes/
users/
index.tsx → /api/users
packages/
docs/
routes/
index.tsx → /docs
shop/
routes/
index.tsx → /shop
`

Routes from each mount stay isolated when resolving parents and dot-flattening, but still merged into a single manifest.

Recipes

$3

For a CMS-style setup where you want a homepage (/) and a catch-all for dynamic pages (/*), use a separate index.tsx and $.tsx.

`
routes/
├── index.tsx → Homepage (/)
└── $.tsx → Catch-all (/*)
`

Why?
Using an optional splat ($).tsx can cause issues with error boundaries bubbling up unexpectedly in React Router v7. Separating them ensures:

1. The homepage has its own explicit route and data requirements.
2. The catch-all route handles everything else (404s or dynamic CMS pages) without interfering with the root layout's error handling.

Migration Guide

> Note: This migration tool is designed for projects using remix-flat-routes 0.8.\*

This library preserves remix-flat-routes sibling behavior: dot-delimited routes remain siblings by default and only nest under explicit layout files (_layout.tsx or layout.tsx).

If you want edit to render inside a layout, add a layout file and (optionally) move the detail view to index.tsx:

`
routes/
└── users/
└── $id/
├── _layout.tsx → Layout for /users/:id/*
├── index.tsx → /users/:id (The detail view)
└── edit.tsx → /users/:id/edit (The edit view)
`

The migration tool continues to follow legacy remix-flat-routes semantics and will promote parent routes to _layout when children exist.

$3

Ensure your project already lists typescript@>=5.0; the CLI resolves the compiler from your workspace.

Install the package, then run the migration CLI:

`bash
npx migrate-auto-routes

or provide an explicit [source] [destination]


npx migrate-auto-routes app/routes app/new-routes
`

The CLI overwrites the target folder if it already exists. With no arguments it reads from app/routes and writes to app/new-routes. When you pass both arguments, the CLI uses the exact sourceDir and targetDir paths you provide.

Built-in safety checks: The CLI performs these automatically so you don’t have to.

- Verifies you are inside a Git repository and the route source folder (e.g. app/routes) has no pending changes before running the migration CLI
- Runs npx react-router routes before and after rewriting files
- Stages the migrated result in app/new-routes (or your custom target) before swapping it into place
- If successful, renames app/routes to app/old-routes, then moves the new routes into app/routes
- If the generated route output differs, prints a diff, restores the original folder, and keeps the migrated files at the target path for inspection
- When your project still imports createRoutesFromFolders/remix-flat-routes, the CLI updates app/routes.ts to export autoRoutes() so the snapshot check runs against the migrated tree

If everything looks good, you can uninstall the old packages:

`bash
npm uninstall remix-flat-routes
npm uninstall @react-router/remix-routes-option-adapter
`

$3

Deprecating legacy route.tsx files in favor of index.tsx plus + colocation. Support remains for now, after which the matcher will be removed.

If you used route.tsx as the entry point for colocated helpers, follow these steps:

1. Move any colocated assets (loaders, helpers, tests) into a +/ folder so they stay adjacent without being treated as routes.
2. Rename each route.tsx to index.tsx inside its directory so the folder name becomes the route segment.
3. Run npx react-router routes to confirm the manifest compiles cleanly and no lingering route.tsx entries remain. Double-check that colocated helpers stayed inside +/ folders so they are not accidentally exposed as routes.

The migration CLI still recognizes route.tsx right now for backwards compatibility, but future releases will warn (and eventually drop support) once projects have had a full cycle to adopt the index.tsx` pattern.

Requirements

- Node.js >= 20
- React Router v7+

Acknowledgments

This library is heavily inspired by remix-flat-routes by @kiliman. While this is a complete rewrite for React Router v7+, the core routing conventions and ideas stem from that excellent work.