diff --git a/apps/api/tsup.config.ts b/apps/api/tsup.config.ts
index 8422513..858cb8f 100644
--- a/apps/api/tsup.config.ts
+++ b/apps/api/tsup.config.ts
@@ -19,5 +19,12 @@ export default defineConfig({
   // import pointing at engine's un-compiled TS source. (esbuild's tree-shaking
   // can drop this reference when it's unreachable, but that's build-environment
   // dependent — don't rely on it; declare the full transitive closure.)
-  noExternal: ['@meldrank/fairness', '@meldrank/engine', '@meldrank/shared'],
+  //
+  // `@meldrank/rating` has no build output of its own — its package.json
+  // `main`/`exports` point straight at `./src/index.ts` for bundler
+  // consumption only. Left external, the pruned production `node_modules`
+  // resolves that raw `.ts` file and plain `node` refuses to type-strip
+  // anything under `node_modules` (ERR_UNSUPPORTED_NODE_MODULES_TYPE_STRIPPING),
+  // crash-looping the service at boot.
+  noExternal: ['@meldrank/fairness', '@meldrank/engine', '@meldrank/rating', '@meldrank/shared'],
 });