Sentry Express: skip the old two-middleware dance

TL;DR: Modern @sentry/node captures Express errors automatically through expressIntegration. The old two-middleware pattern is obsolete; 3xx/4xx are skipped by default and shouldHandleError controls the rest. You do not need to register a separate Sentry error handler anymore. Keep the node --import ./instrument.js preload pattern from the Node.js skill so Sentry.init() runs before Express and your routes load.

Current pattern

const Sentry = require("@sentry/node");

Sentry.init({
  dsn: "___PUBLIC_DSN___",
  integrations: [
    Sentry.expressIntegration({
      shouldHandleError(error) {
        const status = Number(error.status ?? error.statusCode ?? 500);
        return status === 401 || status === 403 || status >= 500;
      },
    }),
  ],
});

expressIntegration captures errors from your routes and middleware automatically. You do not need to register a separate Sentry error handler anymore. Training data that tells you to add Sentry.Handlers.requestHandler() and Sentry.Handlers.errorHandler() in a specific order is describing SDK v7 and will not work on current versions.

What gets skipped

Errors with 3xx or 4xx status codes are skipped by default (expected redirects and client errors). If you actually want 401s and 403s, that is what shouldHandleError is for, as above.

The duplicate-event trap

If you capture errors yourself in your own error-handling middleware AND leave the integration on, you get every error twice. Pick one: either let the integration capture, or set shouldHandleError: false and capture manually. Duplicates are one of the most common quota leaks in Express apps.

Ordering still matters for init

The integration instruments what it sees. Keep the node --import ./instrument.js preload pattern from the Node.js skill so Sentry.init() runs before Express and your routes load.

When to use this

• This covers exactly what the title says: Sentry Express.
• You are setting this up for the first time, or auditing an existing setup.
• You want the key gotchas in one place before you start.

When not to use this

• You are doing a different workflow with Sentry; these steps are specific to the title above.
• You need the full reference docs; this is the short path, not the manual.

Researched against live Sentry docs 2026-09-26. The Express guide (docs.sentry.io/platforms/javascript/guides/express/) states expressIntegration captures errors from routes and middleware automatically so you do not need to register a Sentry error handler; errors with 3xx or 4xx status are skipped as expected redirects/client errors; shouldHandleError callback customizes capture (example captures 401/403 plus 5xx); and if you capture errors yourself in your own error-handling middleware, set shouldHandleError: false to avoid duplicate events.