From 3768aa95b644a4b3592fae289072b3662d9573b5 Mon Sep 17 00:00:00 2001
From: s1gr1d <32902192+s1gr1d@users.noreply.github.com>
Date: Wed, 21 Oct 2026 10:41:57 +0200
Subject: [PATCH] fix(build): Make CJS re-exports visible to Node ESM imports
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When plain Node ESM code imports `@sentry/nextjs`, Node loads the CJS build, because the `node` export condition points to it. Namespace imports then miss about 180 exports (`captureException`, `setUser`, …), which are silently `undefined`.

Rollup writes `export *` in CJS as a loop with an arrow function, but Node only recognizes that loop with a `function` callback. So Node can't see the `@sentry/node` re-exports. Fixed by turning off arrow functions in Rollup's generated helpers.

- Only that loop changes, and only in CJS output. ESM output and CDN bundles are unchanged, so size-limit is not affected.
- Also fixes `@sentry/remix`, which pins `node` to CJS too.
- On Node 20, 22 and 24, namespace imports now match `require()`. Bun and Deno were not affected.
- Splitting the `node` condition is not needed for this fix and is still blocked (see #23628).
- Supersedes #25378, which re-exports only 8 of the missing names.

A unit test checks that Node sees the `@sentry/node` re-export.

Fixes #22791
---
 dev-packages/rollup-utils/npmHelpers.mjs   |  2 ++
 packages/nextjs/test/serverExports.test.ts | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/dev-packages/rollup-utils/npmHelpers.mjs b/dev-packages/rollup-utils/npmHelpers.mjs
index a113feb1aa75..7d1d7b794eef 100644
--- a/dev-packages/rollup-utils/npmHelpers.mjs
+++ b/dev-packages/rollup-utils/npmHelpers.mjs
@@ -108,6 +108,8 @@ export function makeBaseNPMConfig(options = {}) {
       // Allow wrappers or helper functions generated by rollup to use any ES2015 features
       generatedCode: {
         preset: 'es2015',
+        // With arrow functions, Node can't see `export *` exports when ESM code imports our CJS files.
+        arrowFunctions: false,
       },
 
       // don't add `"use strict"` to the top of cjs files
diff --git a/packages/nextjs/test/serverExports.test.ts b/packages/nextjs/test/serverExports.test.ts
index 558c890e93b8..caeb99569498 100644
--- a/packages/nextjs/test/serverExports.test.ts
+++ b/packages/nextjs/test/serverExports.test.ts
@@ -35,3 +35,17 @@ describe('Node-only integrations are statically detectable exports from every ru
     },
   );
 });
+
+/**
+ * Node loads this CJS file for ESM imports too, and must see that it re-exports everything from `@sentry/node`.
+ *
+ * Regression test for https://github.com/getsentry/sentry-javascript/issues/22791
+ */
+describe('CJS server build re-exports are detectable by Node', () => {
+  it('detects the `@sentry/node` re-export', async () => {
+    await init();
+    const { reexports } = parse(readFileSync(resolve(__dirname, '../build/cjs/index.server.js'), 'utf8'));
+
+    expect(reexports).toContain('@sentry/node');
+  });
+});