NathanDrake2406 · NathanDrake2406 · Jun 4, 2026
diff --git a/packages/vinext/src/index.ts b/packages/vinext/src/index.ts
@@ -149,6 +149,7 @@ import {
 import { stripServerExports } from "./plugins/strip-server-exports.js";
 import { removeConsoleCalls } from "./plugins/remove-console.js";
 import { createImportMetaUrlPlugin } from "./plugins/import-meta-url.js";
+import { createIgnoreDynamicRequestsPlugin } from "./plugins/ignore-dynamic-requests.js";
 import { hasMdxFiles } from "./utils/mdx-scan.js";
 import { scanPublicFileRoutes } from "./utils/public-routes.js";
 import { getViteMajorVersion } from "./utils/vite-version.js";
@@ -982,6 +983,10 @@ export default function vinext(options: VinextOptions = {}): PluginOption[] {
     ...(viteMajorVersion >= 8 ? [] : [tsconfigPaths()]),
     // React Fast Refresh + JSX transform for client components.
     reactPluginPromise,
+    // Next.js/Turbopack ignores "very dynamic" requests with no static path
+    // part during graph analysis. Preserve that behaviour before the CJS
+    // plugin tries to expand require(dynamic) as a static glob.
+    createIgnoreDynamicRequestsPlugin(),
     // Transform CJS require()/module.exports to ESM before other plugins
     // analyze imports (RSC directive scanning, shim resolution, etc.)
     commonjs(),

diff --git a/packages/vinext/src/plugins/ignore-dynamic-requests.ts b/packages/vinext/src/plugins/ignore-dynamic-requests.ts
@@ -0,0 +1,230 @@
+import path from "node:path";
+import MagicString from "magic-string";
+import type { Plugin } from "vite";
+import { parseAst } from "vite";
+
+const MODULE_EXTENSIONS = new Set([".cjs", ".mjs", ".js", ".cts", ".mts", ".ts", ".jsx", ".tsx"]);
+const DYNAMIC_REQUIRE_HELPER_BASE = "__vinext_ignored_dynamic_require__";
+
+type AstRecord = {
+  type: string;
+  start?: number;
+  end?: number;
+  [key: string]: unknown;
+};
+
+type TransformResult = {
+  code: string;
+  map: ReturnType<MagicString["generateMap"]>;
+};
+
+type ParserLang = "js" | "jsx" | "ts" | "tsx";
+
+function getObjectProperty(value: unknown, key: string): unknown {
+  if (typeof value !== "object" || value === null) return null;
+  return Reflect.get(value, key);
+}
+
+function isAstRecord(value: unknown): value is AstRecord {
+  return typeof getObjectProperty(value, "type") === "string";
+}
+
+function toAstRecord(value: unknown): AstRecord | null {
+  return isAstRecord(value) ? value : null;
+}
+
+function astArray(value: unknown): AstRecord[] {
+  if (!Array.isArray(value)) return [];
+  return value.flatMap((entry) => {
+    const node = toAstRecord(entry);
+    return node ? [node] : [];
+  });
+}
+
+function hasRange(node: AstRecord | null): node is AstRecord & { start: number; end: number } {
+  return node !== null && typeof node.start === "number" && typeof node.end === "number";
+}
+
+function walkAst(value: unknown, visit: (node: AstRecord) => void): void {
+  if (Array.isArray(value)) {
+    for (const item of value) {
+      walkAst(item, visit);
+    }
+    return;
+  }
+
+  const node = toAstRecord(value);
+  if (!node) return;
+
+  visit(node);
+
+  for (const [key, child] of Object.entries(node)) {
+    if (key === "parent") continue;
+    walkAst(child, visit);
+  }
+}
+
+function isIdentifierNamed(node: AstRecord | null, name: string): boolean {
+  return node?.type === "Identifier" && node.name === name;
+}
+
+function firstArgument(node: AstRecord): AstRecord | null {
+  return astArray(node.arguments)[0] ?? null;
+}
+
+function templateElementHasStaticPart(node: AstRecord): boolean {
+  const raw = getObjectProperty(node.value, "raw");
+  const cooked = getObjectProperty(node.value, "cooked");
+  return (
+    (typeof raw === "string" && raw.length > 0) || (typeof cooked === "string" && cooked.length > 0)
+  );
+}
+
+function requestHasStaticPart(node: AstRecord | null): boolean {
+  if (!node) return false;
+
+  if (node.type === "Literal" || node.type === "StringLiteral") {
+    return typeof node.value === "string" && node.value.length > 0;
+  }
+
+  if (node.type === "TemplateLiteral") {
+    return astArray(node.quasis).some(templateElementHasStaticPart);
+  }
+
+  if (
+    node.type === "BinaryExpression" ||
+    node.type === "LogicalExpression" ||
+    node.type === "ConditionalExpression"
+  ) {
+    return (
+      requestHasStaticPart(toAstRecord(node.left)) ||
+      requestHasStaticPart(toAstRecord(node.right)) ||
+      requestHasStaticPart(toAstRecord(node.consequent)) ||
+      requestHasStaticPart(toAstRecord(node.alternate))
+    );
+  }
+
+  return false;
+}
+
+function isVeryDynamicRequireCall(node: AstRecord): boolean {
+  if (node.type !== "CallExpression") return false;
+  if (!isIdentifierNamed(toAstRecord(node.callee), "require")) return false;
+  return !requestHasStaticPart(firstArgument(node));
+}
+
+function isVeryDynamicImportExpression(node: AstRecord): boolean {
+  if (node.type !== "ImportExpression") return false;
+  return !requestHasStaticPart(toAstRecord(node.source));
+}
+
+function directiveInsertionPoint(body: unknown): number {
+  let insertionPoint = 0;
+
+  for (const node of astArray(body)) {
+    if (node.type !== "ExpressionStatement") break;
+    const expression = toAstRecord(node.expression);
+    if (
+      expression?.type !== "Literal" ||
+      typeof expression.value !== "string" ||
+      typeof node.end !== "number"
+    ) {
+      break;
+    }
+    insertionPoint = node.end;
+  }
+
+  return insertionPoint;
+}
+
+function uniqueHelperName(code: string): string {
+  let helperName = DYNAMIC_REQUIRE_HELPER_BASE;
+  let suffix = 0;
+
+  while (code.includes(helperName)) {
+    suffix += 1;
+    helperName = `${DYNAMIC_REQUIRE_HELPER_BASE}${suffix}`;
+  }
+
+  return helperName;
+}
+
+function cleanModuleId(id: string): string {
+  return id.split(/[?#]/, 1)[0] ?? id;
+}
+
+function parserLangForId(id: string): ParserLang {
+  const extension = path.extname(cleanModuleId(id));
+  if (extension === ".jsx") return "jsx";
+  if (extension === ".ts" || extension === ".tsx" || extension === ".cts" || extension === ".mts") {
+    return extension === ".tsx" ? "tsx" : "ts";
+  }
+  return "js";
+}
+
+function isTransformableModuleId(id: string): boolean {
+  const cleanId = cleanModuleId(id);
+  if (cleanId.includes("/node_modules/")) return false;
+  return MODULE_EXTENSIONS.has(path.extname(cleanId));
+}
+
+function ignoreVeryDynamicRequests(code: string, id: string): TransformResult | null {
+  if (!/\b(?:import|require)\s*\(/.test(code)) return null;
+
+  let ast: ReturnType<typeof parseAst>;
+  try {
+    ast = parseAst(code, { lang: parserLangForId(id) }, cleanModuleId(id));
+  } catch {
+    return null;
+  }
+
+  const output = new MagicString(code);
+  const helperName = uniqueHelperName(code);
+  let rewroteRequire = false;
+  let changed = false;
+
+  walkAst(ast.body, (node) => {
+    if (isVeryDynamicRequireCall(node)) {
+      const callee = toAstRecord(node.callee);
+      if (!hasRange(callee)) return;
+      output.overwrite(callee.start, callee.end, helperName);
+      rewroteRequire = true;
+      changed = true;
+      return;
+    }
+
+    if (isVeryDynamicImportExpression(node)) {
+      const source = toAstRecord(node.source);
+      if (!hasRange(source)) return;
+      if (code.slice(node.start ?? 0, source.start).includes("@vite-ignore")) return;
+      output.appendLeft(source.start, "/* @vite-ignore */ ");
+      changed = true;
+    }
+  });
+
+  if (!changed) return null;
+
+  if (rewroteRequire) {
+    const insertionPoint = directiveInsertionPoint(ast.body);
+    output.appendRight(
+      insertionPoint,
+      `\nfunction ${helperName}(id) {\n  throw new Error("Cannot find module " + String(id));\n}\n`,
+    );
+  }
+
+  return {
+    code: output.toString(),
+    map: output.generateMap({ hires: true, source: id }),
+  };
+}
+
+export function createIgnoreDynamicRequestsPlugin(): Plugin {
+  return {
+    name: "vinext:ignore-dynamic-requests",
+    enforce: "pre",
+    transform(code, id) {
+      if (!isTransformableModuleId(id)) return null;
+      return ignoreVeryDynamicRequests(code, id);
+    },
+  };
+}
diff --git a/tests/build-optimization.test.ts b/tests/build-optimization.test.ts
@@ -2137,6 +2137,111 @@ export const getStaticPaths = () => [
   });
 });
 
+// ─── App Router build compatibility ──────────────────────────────────────────
+
+describe("App Router build compatibility", () => {
+  // Ported from Next.js: test/e2e/app-dir/dynamic-requests/dynamic-requests.test.ts
+  // https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/dynamic-requests/dynamic-requests.test.ts
+  it("builds page and route modules with guarded very dynamic import and require calls", async () => {
+    const vinext = (await import("../packages/vinext/src/index.js")).default;
+    const tmpDir = await fsp.mkdtemp(path.join(os.tmpdir(), "vinext-dynamic-requests-build-"));
+    const rootNodeModules = path.resolve(import.meta.dirname, "../node_modules");
+    await fsp.symlink(rootNodeModules, path.join(tmpDir, "node_modules"), "junction");
+
+    const writeFile = async (filePath: string, content: string) => {
+      const absPath = path.join(tmpDir, filePath);
+      await fsp.mkdir(path.dirname(absPath), { recursive: true });
+      await fsp.writeFile(absPath, content);
+    };
+
+    try {
+      await writeFile(
+        "package.json",
+        JSON.stringify({ name: "vinext-dynamic-requests-build", private: true, type: "module" }),
+      );
+      await writeFile(
+        "tsconfig.json",
+        JSON.stringify(
+          {
+            compilerOptions: {
+              target: "ES2022",
+              module: "ESNext",
+              moduleResolution: "bundler",
+              jsx: "react-jsx",
+              strict: true,
+              skipLibCheck: true,
+              types: ["vite/client", "@vitejs/plugin-rsc/types"],
+            },
+            include: ["app", "*.ts", "*.tsx"],
+          },
+          null,
+          2,
+        ),
+      );
+      await writeFile(
+        "app/layout.tsx",
+        `import type { ReactNode } from "react";
+
+export default function RootLayout({ children }: { children: ReactNode }) {
+  return (
+    <html lang="en">
+      <body>{children}</body>
+    </html>
+  );
+}
+`,
+      );
+
+      const guardedDynamicRequest = `function dynamic() {
+  const dynamic = Math.random() + "";
+  require(dynamic);
+  import(dynamic);
+}
+`;
+
+      await writeFile(
+        "app/page.tsx",
+        `export default async function Page() {
+  if (Math.random() < 0) dynamic();
+  return <p>Hello World</p>;
+}
+
+${guardedDynamicRequest}`,
+      );
+      await writeFile(
+        "app/hello/route.tsx",
+        `export function GET() {
+  if (Math.random() < 0) dynamic();
+  return new Response("Hello World");
+}
+
+${guardedDynamicRequest}`,
+      );
+
+      const rscOutDir = path.join(tmpDir, "dist", "server");
+      const ssrOutDir = path.join(tmpDir, "dist", "server", "ssr");
+      const clientOutDir = path.join(tmpDir, "dist", "client");
+      const builder = await createBuilder({
+        root: tmpDir,
+        configFile: false,
+        plugins: [vinext({ appDir: tmpDir, rscOutDir, ssrOutDir, clientOutDir })],
+        logLevel: "silent",
+      });
+      await builder.buildApp();
+
+      await expect(fsp.access(path.join(tmpDir, "dist", "server", "index.js"))).resolves.toBe(
+        undefined,
+      );
+      await expect(
+        fsp.access(path.join(tmpDir, "dist", "server", "ssr", "index.js")),
+      ).resolves.toBe(undefined);
+      await expect(fsp.access(path.join(tmpDir, "dist", "client"))).resolves.toBe(undefined);
+    } finally {
+      await fsp.rm(tmpDir, { recursive: true, force: true }).catch(() => {});
+    }
+  }, 60_000);
+});
+
 // ─── getClientTreeshakeConfigForVite ──────────────────────────────────────────
 
 describe("getClientTreeshakeConfigForVite", () => {