Vercel / Deployment

How to Fix Vercel MIDDLEWARE_INVOCATION_FAILED Cannot Find Module @swc/helpers in Next.js 16

Fix Vercel deployment failure with MIDDLEWARE_INVOCATION_FAILED and missing @swc/helpers module in Next.js 16 middleware Includes evidence for Vercel troubleshooting demand.

Source-backed Last updated May 15, 2026 1 source Needs local verification

Category: Deployment
Error signature: MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js'
Quick fix: Check the build output, project root, and deployment platform configuration before redeploying.
Updated: May 15, 2026
Verification status: Source-backed
Evidence: 1 public source URL

Before you change production

This page includes public source URLs in the imported troubleshooting record. Compare those references with your version and environment before applying changes.

Reproduce the smallest failing action and save non-secret logs before changing configuration.
Check versions for Vercel, related SDKs, package managers, CI runners, and hosting providers.
Change one setting or dependency at a time, then rerun the same failing command or request.
Avoid destructive commands, credential rotation, billing changes, or security relaxations without a rollback plan.

What this error means

MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js' is a Vercel failure pattern reported for developers trying to fix vercel deployment failure with middleware_invocation_failed and missing @swc/helpers module in next.js 16 middleware. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue vercel/next.js#93852 (May 14, 2026): Next.js 16.2.6 with proxy.ts middleware and top-level @sentry/nextjs import causes MIDDLEWARE_INVOCATION_FAILED on Vercel deploy. Local build passes, Vercel runtime fails. The @swc/helpers ESM path exists in node_modules but Vercel's runtime resolver cannot find it. Removing Sentry import fixes deploy. Category: Deployment (Vercel is the deployment platform).

Common causes

GitHub issue vercel/next.js#93852 (May 14, 2026): Next.js 16.2.6 with proxy.ts middleware and top-level @sentry/nextjs import causes MIDDLEWARE_INVOCATION_FAILED on Vercel deploy. Local build passes, Vercel runtime fails. The @swc/helpers ESM path exists in node_modules but Vercel's runtime resolver cannot find it. Removing Sentry import fixes deploy. Category: Deployment (Vercel is the deployment platform).

Quick fixes

Confirm the exact error signature matches MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js'.
Check the Vercel account, local tool state, and provider configuration involved in the failing workflow.
Check the build output, project root, and deployment platform configuration before redeploying.

Platform/tool-specific checks

Verify the command, editor, extension, or API client that produced the error.
Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

Capture the exact error message and the command, editor action, or request that triggered it.
Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
Review the source evidence below and compare it with your environment.
Apply one change at a time and rerun the smallest failing action.
Keep the working fix documented for the team or deployment environment.

How to prevent it

Keep provider/tool configuration documented.
Record non-secret diagnostics such as tool version, provider name, model name, and command path.
Add a lightweight check before CI or production workflows depend on the tool.

Diagnostic flow for this page

Match MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js' exactly before applying the quick fix.
Compare the failing environment with Vercel versions, account scope, provider settings, and deployment context.
Check the listed common causes in order, starting with the cause that best matches your logs.
Use the evidence status below to decide whether to confirm against public sources or official documentation.
Apply one reversible change, rerun the smallest failing action, and keep rollback notes.

FAQ

What does MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js' mean in Vercel?

MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js' indicates the workflow described by "How to Fix Vercel MIDDLEWARE_INVOCATION_FAILED Cannot Find Module @swc/helpers in Next.js 16" failed in a Deployment context. Start by confirming the exact signature and the component that emitted it.

What should I check first for MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js'?

Check whether this cause matches your environment: GitHub issue vercel/next.js#93852 (May 14, 2026): Next.js 16.2.6 with proxy.ts middleware and top-level @sentry/nextjs import causes MIDDLEWARE_INVOCATION_FAILED on Vercel deploy. Local build passes, Vercel runtime fails. The @swc/helpers ESM path exists in node_modules but Vercel's runtime resolver cannot find it. Removing Sentry import fixes deploy. Category: Deployment (Vercel is the deployment platform).

Is the MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js' guidance source-backed?

The "How to Fix Vercel MIDDLEWARE_INVOCATION_FAILED Cannot Find Module @swc/helpers in Next.js 16" page is labeled source-backed. It has 1 public source URL from github.com, so use that evidence status when deciding how much additional verification you need.

When should I avoid the quick fix for MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js'?

For "How to Fix Vercel MIDDLEWARE_INVOCATION_FAILED Cannot Find Module @swc/helpers in Next.js 16", avoid applying "Check the build output, project root, and deployment platform configuration before redeploying." when the error text differs, the affected version or provider is different, or the change would touch credentials, billing, DNS, production deploy settings, or irreversible data.

What should I collect before debugging MIDDLEWARE_INVOCATION_FAILED: Cannot find module '/var/task/node_modules/@swc/helpers/esm/_interop_require_default.js'?

For "How to Fix Vercel MIDDLEWARE_INVOCATION_FAILED Cannot Find Module @swc/helpers in Next.js 16", collect the failing Vercel command or request, non-secret configuration, versions, timestamps, request IDs when available, and the smallest reproduction that still triggers the signature.