@@ -28,11 +28,43 @@ export type DeploySourceMetadata = {
   gitRef: string | null;
 };
 
-/** JSON payload accepted by the managed deployment API. */
+/** One Worker module uploaded to R2 before the deployment is finalized. */
+export type DeployWorkerModule = {
+  /** Module path relative to the Worker output, the same key `workerFiles` uses. */
+  name: string;
+  /** Byte length of the module. */
+  size: number;
+  /** SHA-256 of the module bytes as 64 lowercase hex characters. */
+  sha256: string;
+};
+
+/** Request body of `POST /projects/:id/deploy/worker-upload-urls`. */
+export type DeployWorkerUploadRequest = {
+  modules: Array<DeployWorkerModule>;
+};
+
+/** Upload URLs for each requested module, in request order. */
+export type DeployWorkerUploadResponse = {
+  id: string;
+  urls: Array<{ url: string; headers: Record<string, string> }>;
+};
+
+/** Worker modules already uploaded through `worker-upload-urls`, named by its upload `id`. */
+export type DeployWorkerInput = {
+  id: string;
+  modules: Array<DeployWorkerModule>;
+};
+
+/**
+ * JSON payload accepted by the managed deployment API. Worker modules travel
+ * either inline as `workerFiles` or uploaded beforehand as `workerInput`,
+ * never both.
+ */
 export type DeployUploadPayload = {
   manifest: DeployManifest;
   assetManifest: Record<string, DeployAssetManifestEntry>;
   workerFiles?: Record<string, string>;
+  workerInput?: DeployWorkerInput;
 } & DeploySourceMetadata & {
     preflight: 'true' | null;
   };
@@ -61,15 +93,31 @@ export function createDeployArtifact(input: {
   };
 }
 
-/** Convert the canonical artifact into the stable hosted-platform wire shape. */
+/**
+ * Convert the canonical artifact into the stable hosted-platform wire shape.
+ * Pass `workerInput` when the Worker modules were uploaded beforehand; the
+ * artifact must then carry no inline `workerFiles`.
+ */
 export function createDeployUploadPayload(
   artifact: DeployArtifact,
   metadata: DeploySourceMetadata & { preflight: 'true' | null },
+  workerInput?: DeployWorkerInput,
 ): DeployUploadPayload {
+  if (workerInput && artifact.workerFiles) {
+    throw new Error('A deployment sends its Worker modules inline or as uploads, not both.');
+  }
   return {
     manifest: { ...artifact.manifest, bindings: { ...artifact.manifest.bindings } },
     assetManifest: { ...artifact.assetManifest },
     ...(artifact.workerFiles ? { workerFiles: { ...artifact.workerFiles } } : {}),
+    ...(workerInput
+      ? {
+          workerInput: {
+            id: workerInput.id,
+            modules: workerInput.modules.map((module) => ({ ...module })),
+          },
+        }
+      : {}),
     ...metadata,
   };
 }
@@ -338,6 +338,10 @@ export type {
   DeployAssetUploadRequest,
   DeploySourceMetadata,
   DeployUploadPayload,
+  DeployWorkerInput,
+  DeployWorkerModule,
+  DeployWorkerUploadRequest,
+  DeployWorkerUploadResponse,
 } from './artifact.ts';
 export {
   DEPLOY_ARTIFACT_VERSION,
 
@@ -57,4 +57,38 @@ describe('deployment artifacts', () => {
     });
     expect(payload).not.toHaveProperty('artifactVersion');
   });
+
+  it('names uploaded Worker modules by workerInput instead of carrying their bytes', () => {
+    const metadata = {
+      source: 'cli',
+      commit: null,
+      repositoryUrl: null,
+      commitUrl: null,
+      gitRef: null,
+      preflight: null,
+    };
+    const workerInput = {
+      id: 'upload-1',
+      modules: [{ name: 'index.js', size: 18, sha256: 'a'.repeat(64) }],
+    };
+    const payload = createDeployUploadPayload(
+      createDeployArtifact({ manifest, assetManifest: {} }),
+      metadata,
+      workerInput,
+    );
+
+    expect(payload.workerInput).toEqual(workerInput);
+    expect(payload).not.toHaveProperty('workerFiles');
+    expect(() =>
+      createDeployUploadPayload(
+        createDeployArtifact({
+          manifest,
+          assetManifest: {},
+          workerFiles: { 'index.js': 'ZXhwb3J0IGRlZmF1bHQge30=' },
+        }),
+        metadata,
+        workerInput,
+      ),
+    ).toThrow('not both');
+  });
 });
@@ -29,6 +29,11 @@ export type PlatformDiscoveryDocument = Readonly<{
   capabilities: PlatformCapabilities;
   displayName: string;
   dashboardUrl?: string;
+  /**
+   * The API accepts Worker modules uploaded to R2 through
+   * `POST /projects/:id/deploy/worker-upload-urls`. Older platforms omit it.
+   */
+  directWorkerUpload?: boolean;
   installationId: string | null;
   platformVersion: string;
   proxyUrl: string;
@@ -54,11 +59,24 @@ function normalizeOrigin(value: string, name: 'apiUrl' | 'proxyUrl'): string {
   return url.origin;
 }
 
+type PlatformDiscoveryInput = Omit<
+  PlatformDiscoveryDocument,
+  'directWorkerUpload' | 'schemaVersion' | 'usageProtocolVersion'
+> & {
+  usageProtocolVersion?: 0 | 1 | 2;
+};
+
+/**
+ * Builds the document a platform serves at `/.well-known/void-platform`.
+ * Every platform built from this source accepts direct Worker uploads.
+ */
 export function createPlatformDiscoveryDocument(
-  input: Omit<PlatformDiscoveryDocument, 'schemaVersion' | 'usageProtocolVersion'> & {
-    usageProtocolVersion?: 0 | 1 | 2;
-  },
+  input: PlatformDiscoveryInput,
 ): PlatformDiscoveryDocument {
+  return { ...normalizeDiscoveryDocument(input), directWorkerUpload: true };
+}
+
+function normalizeDiscoveryDocument(input: PlatformDiscoveryInput): PlatformDiscoveryDocument {
   if (!input.displayName.trim()) {
     throw new Error('displayName must not be empty.');
   }
@@ -195,7 +213,11 @@ export function parsePlatformDiscoveryDocument(value: unknown): PlatformDiscover
   };
   const apiUrl = string('apiUrl');
   const proxyUrl = string('proxyUrl');
-  return createPlatformDiscoveryDocument({
+  const directWorkerUpload = document.directWorkerUpload;
+  if (directWorkerUpload !== undefined && typeof directWorkerUpload !== 'boolean') {
+    throw new Error('directWorkerUpload must be a boolean.');
+  }
+  const parsed = normalizeDiscoveryDocument({
     apiUrl,
     applicationDomain: string('applicationDomain'),
     ...(document.applicationRouting !== undefined
@@ -213,6 +235,8 @@ export function parsePlatformDiscoveryDocument(value: unknown): PlatformDiscover
     proxyUrl,
     usageProtocolVersion: parseUsageProtocolVersion(document.usageProtocolVersion),
   });
+  // Report only what the platform said: an older platform omits the field.
+  return directWorkerUpload === undefined ? parsed : { ...parsed, directWorkerUpload };
 }
 
 function parseAuthentication(value: unknown): PlatformAuthenticationDiscovery {
 
@@ -110,3 +110,24 @@ describe('authentication discovery compatibility', () => {
     expect(JSON.stringify(parsed.authentication)).not.toContain('internal.example.com');
   });
 });
+
+describe('direct Worker upload discovery', () => {
+  it('advertises direct Worker uploads on every document this platform serves', () => {
+    for (const input of [base, modern]) {
+      const discovery = createPlatformDiscoveryDocument(input);
+      expect(discovery.directWorkerUpload).toBe(true);
+      expect(parsePlatformDiscoveryDocument(discovery)).toEqual(discovery);
+    }
+  });
+
+  it('reports only what an older platform said', () => {
+    const { directWorkerUpload: _, ...older } = createPlatformDiscoveryDocument(base);
+    expect(parsePlatformDiscoveryDocument(older)).not.toHaveProperty('directWorkerUpload');
+    expect(
+      parsePlatformDiscoveryDocument({ ...older, directWorkerUpload: false }).directWorkerUpload,
+    ).toBe(false);
+    expect(() => parsePlatformDiscoveryDocument({ ...older, directWorkerUpload: 'yes' })).toThrow(
+      'directWorkerUpload must be a boolean.',
+    );
+  });
+});
@@ -13,7 +13,14 @@ import {
   type ProjectPermission,
 } from './platform-errors.ts';
 import { normalizePlatformApiUrl } from './platform-registry.ts';
-import type { DeployAssetUploadRequest, DeployEvent, DeployUploadPayload } from './types.ts';
+import type {
+  DeployAssetUploadRequest,
+  DeployEvent,
+  DeployUploadPayload,
+  DeployWorkerModule,
+  DeployWorkerUploadRequest,
+  DeployWorkerUploadResponse,
+} from './types.ts';
 
 // Null omits `X-Void-CLI-Version`: the platform answers an unparseable version with 426.
 function readCliVersion(): string | null {
@@ -34,21 +41,22 @@ export const MIN_PLATFORM_VERSION = '1.1.11';
 const RELEASE_VERSION = /^(\d+)\.(\d+)\.(\d+)(-[0-9A-Za-z.-]+)?(\+[0-9A-Za-z.-]+)?$/;
 
 /**
- * Version checks keyed by platform base URL. Every outcome (pass, inconclusive,
- * or too old) is kept for the rest of the process, so polling commands probe
- * discovery once.
+ * Discovery probes keyed by platform base URL. Every outcome (pass,
+ * inconclusive, or too old) is kept for the rest of the process, so polling
+ * commands probe discovery once.
  */
-const platformVersionChecks = new Map<string, Promise<void>>();
+const platformVersionProbes = new Map<string, Promise<PlatformVersionProbe>>();
 
 /**
  * What public discovery says about the platform version:
- * - `version`: the reported `platformVersion`
+ * - `version`: the reported `platformVersion`, and whether the platform
+ *   accepts Worker modules uploaded straight to R2
  * - `missing`: discovery answered 404, so the platform predates discovery
  * - `unknown`: no usable answer (network error, timeout, disabled platform,
  *   Access login page, or an invalid document)
  */
 type PlatformVersionProbe =
-  | { kind: 'version'; version: string }
+  | { kind: 'version'; version: string; directWorkerUpload: boolean }
   | { kind: 'missing' }
   | { kind: 'unknown' };
 
@@ -661,19 +669,34 @@ export class PlatformClient {
 
   /**
    * Checks the platform version once per process and base URL. Concurrent
-   * first requests share one check, and its outcome is kept for later requests.
+   * first requests share one probe, and its outcome is kept for later requests.
    */
-  private ensureSupportedPlatform(): Promise<void> {
-    const apiUrl = this.baseUrl;
-    const cached = platformVersionChecks.get(apiUrl);
+  private async ensureSupportedPlatform(): Promise<void> {
+    assertSupportedPlatform(this.baseUrl, await this.platformProbe());
+  }
+
+  private platformProbe(): Promise<PlatformVersionProbe> {
+    const cached = platformVersionProbes.get(this.baseUrl);
     if (cached) {
       return cached;
     }
-    const check = this.probePlatformVersion().then((probe) =>
-      assertSupportedPlatform(apiUrl, probe),
-    );
-    platformVersionChecks.set(apiUrl, check);
-    return check;
+    const probe = this.probePlatformVersion();
+    platformVersionProbes.set(this.baseUrl, probe);
+    return probe;
+  }
+
+  /**
+   * Whether discovery says the platform accepts Worker modules uploaded to R2.
+   * False when discovery omits the field or gave no usable answer.
+   */
+  async supportsDirectWorkerUpload(): Promise<boolean> {
+    let probe = await this.platformProbe();
+    if (probe.kind === 'unknown') {
+      // One failed probe must not send a large Worker inline. Ask again,
+      // without replacing the outcome the version check keeps.
+      probe = await this.probePlatformVersion();
+    }
+    return probe.kind === 'version' && probe.directWorkerUpload;
   }
 
   /** Reads the platform version from public discovery, without credentials. */
@@ -695,7 +718,11 @@ export class PlatformClient {
     }
     try {
       const discovery = await readPlatformDiscoveryResponse(this.baseUrl, response);
-      return { kind: 'version', version: discovery.platformVersion };
+      return {
+        kind: 'version',
+        version: discovery.platformVersion,
+        directWorkerUpload: discovery.directWorkerUpload === true,
+      };
     } catch {
       return { kind: 'unknown' };
     }
@@ -1117,6 +1144,53 @@ export class PlatformClient {
     return json.urls;
   }
 
+  /**
+   * Requests one presigned R2 PUT per Worker module, in `modules` order. The
+   * platform refuses a Worker over Cloudflare's size limit here (413
+   * `worker_too_large`), before any bytes are uploaded.
+   */
+  async requestWorkerUploadUrls(
+    projectId: string,
+    modules: Array<DeployWorkerModule>,
+  ): Promise<DeployWorkerUploadResponse> {
+    const url = `${this.baseUrl}/projects/${projectId}/deploy/worker-upload-urls`;
+    this.cliLog?.info('worker_upload_urls_post', { url, moduleCount: modules.length });
+
+    const request: DeployWorkerUploadRequest = { modules };
+    const res = await this.request(url, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+        ...this.authHeaders,
+      },
+      body: JSON.stringify(request),
+    });
+    this.cliLog?.info('worker_upload_urls_response', {
+      status: res.status,
+      cfRay: res.headers.get('cf-ray'),
+    });
+
+    if (!res.ok) {
+      await throwPlatformApiError('Failed to request worker upload URLs', res, 'deploy');
+    }
+
+    // Module i uploads to urls[i], so a short or malformed list must not start.
+    const json = (await res.json()) as Partial<DeployWorkerUploadResponse> | null;
+    if (
+      typeof json?.id !== 'string' ||
+      !json.id ||
+      !Array.isArray(json.urls) ||
+      json.urls.length !== modules.length ||
+      !json.urls.every(
+        (entry) =>
+          typeof entry?.url === 'string' && typeof entry.headers === 'object' && !!entry.headers,
+      )
+    ) {
+      throw new Error('Invalid worker upload URLs from platform.');
+    }
+    return { id: json.id, urls: json.urls };
+  }
+
   async *finalizeDeploy(
     projectId: string,
     payload: ManifestOnlyDeployPayload,