diff --git a/packages/server/src/server/plugins/compiler.test.ts b/packages/server/src/server/plugins/compiler.test.ts
index dca7d3e3e2..facba48fdb 100644
--- a/packages/server/src/server/plugins/compiler.test.ts
+++ b/packages/server/src/server/plugins/compiler.test.ts
@@ -455,6 +455,33 @@ export type Value = string;`,
     expect(serverBundle).not.toContain("Client contribution");
   });
 
+  it.each(["main", "module"])(
+    "builds a dependency that declares only %s into both runtimes",
+    async (field) => {
+      const entries = await createSplitPlugin();
+      const dependency = path.join(entries.directory, "node_modules/legacy-entry");
+      await mkdir(dependency, { recursive: true });
+      await writeFile(
+        path.join(dependency, "package.json"),
+        JSON.stringify({ name: "legacy-entry", [field]: "lib/entry.js" }),
+      );
+      await mkdir(path.join(dependency, "lib"));
+      await writeFile(
+        path.join(dependency, "lib/entry.js"),
+        'exports.label = "legacy entry contribution";',
+      );
+      await writeFile(
+        path.join(entries.directory, "shared/labels.ts"),
+        'import { label } from "legacy-entry"; export const clientLabel = label; export const serverLabel = label;',
+      );
+
+      const { clientBundle, serverBundle } = await compilePlugin(entries);
+
+      expect(clientBundle).toContain("legacy entry contribution");
+      expect(serverBundle).toContain("legacy entry contribution");
+    },
+  );
+
   it("uses the automatic JSX runtime without a React import", async () => {
     const entries = await createSplitPlugin();
     const { clientBundle } = await compilePlugin(entries);
diff --git a/packages/server/src/server/plugins/compiler.ts b/packages/server/src/server/plugins/compiler.ts
index 80dbb1b7b0..15df395d06 100644
--- a/packages/server/src/server/plugins/compiler.ts
+++ b/packages/server/src/server/plugins/compiler.ts
@@ -391,6 +391,10 @@ async function compileTarget(entryPath: string, target: PluginBuildTarget): Prom
     jsx: "automatic",
     platform: target === "server" ? "node" : "neutral",
     target: target === "server" ? "node20" : "es2020",
+    // The neutral platform reads no package.json entry fields, so packages without
+    // `exports` would not resolve. Read the same fields as esbuild's browser platform
+    // minus `browser`, since the bundle also runs in React Native.
+    mainFields: target === "client" ? ["module", "main"] : undefined,
     // Metro lowers async syntax before Hermes sees app code. Plugin client bundles bypass Metro,
     // so apply the same compatibility transform before the app evaluates them from source.
     supported: target === "client" ? { "async-await": false } : undefined,