remix-run/remix · error · Error

Route-map loader returned an invalid route leaf for "${name}

Error message

Route-map loader returned an invalid route leaf for "${name}".

What it means

For 'route' kind nodes, `method` and `pattern` must both be strings; they define the HTTP route leaf. This is the last leaf-level validation of the worker payload.

Source

Thrown at packages/cli/src/lib/route-map.ts:271

  if (!Array.isArray(children)) {
    throw new Error(`Route-map loader returned invalid children for "${name}".`)
  }

  if (kind === 'group') {
    return {
      children: children.map((child) => assertRawRouteTreeNode(child)),
      key,
      kind,
      name,
    }
  }

  let method = Reflect.get(value, 'method')
  let pattern = Reflect.get(value, 'pattern')

  if (typeof method !== 'string' || typeof pattern !== 'string') {
    throw new Error(`Route-map loader returned an invalid route leaf for "${name}".`)
  }

  return {
    children: [],
    key,
    kind,
    method,
    name,
    pattern,
  }
}

async function findRemixAppRoot(startDir: string): Promise<string> {
  let appRoot = await findAppRoot(startDir, 'app/routes.ts')

  if (appRoot == null) {
    throw routesFileNotFound(startDir)
  }

View on GitHub (pinned to 9696913134)

Solutions

1. Align remix package versions and do a clean install
2. Complete route fixtures with string `method` and `pattern` fields
3. If it persists on a clean install, report as a CLI bug

tree.filter(n => n.kind === 'route').every(n => typeof n.method === 'string' && typeof n.pattern === 'string')

function isRouteLeaf(n: unknown): n is { kind: 'route'; method: string; pattern: string } {
  let r = n as any
  return r?.kind === 'route' && typeof r.method === 'string' && typeof r.pattern === 'string'
}

When it happens

Trigger: A route node whose method or pattern is missing/non-string, e.g. `{ kind: 'route', name: 'home' }` with no method/pattern — schema drift or incomplete mock data.

Common situations: Fixture authors omitting method/pattern; mixed-version installs where the leaf schema changed between releases.

Related errors

• Route-map loader returned an invalid route node.
• Route-map loader returned a route node without a valid name.
• Route-map loader returned an unknown node kind for "${name}"
• Route-map loader returned invalid children for "${name}".
• Missing app/routes.ts path.

AI-assisted analysis of remix-run/remix@9696913134 (2026-08-27). Data as JSON: /api/errors/bf8b8547c51d21bb. Report an issue: GitHub.