anomalyco/sst · error · VisibleError

Cannot provide both "domain" and "route". Use the "domain" p

Error message

Cannot provide both "domain" and "route". Use the "domain" prop on the "Router" component when serving your site through a Router.

What it means

When an SSR site is served through a `Router` via the `route` prop, custom domain configuration must live on the Router itself. Passing both `domain` on the site and `route` is ambiguous and rejected at construction time with this message pointing you to set domain on the Router.

Source

Thrown at platform/src/components/aws/ssr-site.ts:1259

            throw new VisibleError(
              `Region ${region} is not supported by this component. Please select a different AWS region.`,
            );

          if (!Object.values(Region).includes(region as Region))
            throw new VisibleError(
              `Invalid AWS region: "${region}". Please specify a valid AWS region.`,
            );
          return region as Region;
        });
      });
    }

    function normalizeRoute() {
      const route = normalizeRouteArgs(args.router, args.route);

      if (route) {
        if (args.domain)
          throw new VisibleError(
            `Cannot provide both "domain" and "route". Use the "domain" prop on the "Router" component when serving your site through a Router.`,
          );

        if (args.edge)
          throw new VisibleError(
            `Cannot provide both "edge" and "route". Use the "edge" prop on the "Router" component when serving your site through a Router.`,
          );

        if (args.protection)
          throw new VisibleError(
            `Cannot set "protection" when routing through a Router. Set "protection" on the Router component instead.`,
          );
      }

      return route;
    }

    function normalizeEdge() {

View on GitHub (pinned to a0bd20f762)

Solutions

Remove the `domain` prop from the site component
Move the domain configuration to the Router component (`new sst.aws.Router("Router", { domain: "example.com" })`)
Deploy again

Example fix

// before
new sst.aws.NextjsSite("Web", {
  path: "src",
  domain: "app.example.com",
  route: { router },
});
// after
new sst.aws.NextjsSite("Web", {
  path: "src",
  route: { router }, // router created with { domain: "app.example.com" }
});

Defensive patterns

Strategy: validation

Validate before calling

if (siteArgs.domain && siteArgs.route) {
  throw new Error('Set `domain` on the Router component instead of the site when using `route`');
}

Try / catch

try {
  new sst.aws.NextjsSite("Web", args);
} catch (e) {
  if (String(e).includes('Cannot provide both "domain" and "route"')) console.error("Move domain to the Router");
  throw e;
}

Prevention

Pick one serving model: standalone (domain) or router-based (route) — not both
When adding a Router, migrate domain config in the same change
Grep site args for `domain:` before enabling route

When it happens

Trigger: An SSR site component args include both `domain: {...}` and `route: { router }` (or `router`), e.g. after partially migrating from domain-based to router-based serving.

Common situations: Following old docs that set `domain` while also adopting a Router; merging config changes where one teammate added a router and another kept the domain.

Related errors

AI-assisted analysis of anomalyco/sst@a0bd20f762 (2026-08-30). Data as JSON: /api/errors/c9ca783dcfc281cc. Report an issue: GitHub.