[prototype] Add experimental config workflow exports

.changeset/experimental-config-workflow-exports.md

@@ -0,0 +1,8 @@
+---
+"wrangler": minor
+"@cloudflare/vite-plugin": minor
+---
+
+Add experimental config support for declarative Workflow exports and cross-Worker Workflow bindings
+
+`cloudflare.config.ts` can now declare owned Workflows with `exports.workflow()`, including step limits and schedules, and create typed external bindings with a referenced Worker's `workflow()` helper. Wrangler deploys and locally simulates these exports, while the Vite plugin recognizes them as `WorkflowEntrypoint` exports.

packages/config/src/__tests__/convert.test.ts

@@ -1,6 +1,8 @@
 import { describe, it } from "vitest";
+import { bindings as bindingConfig } from "../bindings";
 import { convertToWranglerConfig } from "../convert";
 import { exports as exportConfig } from "../exports";
+import { defineWorker } from "../worker-definition";
 
 const baseConfig = { name: "worker", compatibilityDate: "2026-06-01" } as const;
 
@@ -782,6 +784,28 @@ describe("convertToWranglerConfig", () => {
 			});
 		});
 
+		it("passes Workflow exports through", ({ expect }) => {
+			const result = convertToWranglerConfig({
+				...baseConfig,
+				exports: {
+					MyWorkflow: exportConfig.workflow({
+						name: "my-workflow",
+						limits: { steps: 25_000 },
+						schedules: ["0 * * * *"],
+					}),
+				},
+			});
+
+			expect(result.exports).toEqual({
+				MyWorkflow: {
+					type: "workflow",
+					name: "my-workflow",
+					limits: { steps: 25_000 },
+					schedules: ["0 * * * *"],
+				},
+			});
+		});
+
 		it("emits no exports key when the map is empty", ({ expect }) => {
 			const result = convertToWranglerConfig({ ...baseConfig, exports: {} });
 			expect("exports" in (result as object)).toBe(false);
@@ -791,16 +815,56 @@ describe("convertToWranglerConfig", () => {
 			const config = {
 				...baseConfig,
 				exports: {
-					FutureExport: { type: "workflow" },
+					FutureExport: { type: "container" },
 				},
 			} as unknown as Parameters<typeof convertToWranglerConfig>[0];
 
 			expect(() => convertToWranglerConfig(config)).toThrow(
-				/Unknown export types found: - FutureExport : workflow/
+				/Unknown export types found: - FutureExport : container/
 			);
 		});
 	});
 
+	describe("Workflow bindings", () => {
+		it("maps an export-based Workflow binding", ({ expect }) => {
+			const workflowWorker = defineWorker({
+				...baseConfig,
+				name: "workflow-worker",
+				exports: {
+					MyWorkflow: exportConfig.workflow({ name: "my-workflow" }),
+				},
+			});
+			const result = convertToWranglerConfig({
+				...baseConfig,
+				env: {
+					MY_WORKFLOW: workflowWorker.workflow({
+						workerName: "workflow-worker",
+						exportName: "MyWorkflow",
+						remote: true,
+					}),
+					UNTYPED_WORKFLOW: bindingConfig.workflow({
+						workerName: "other-worker",
+						exportName: "OtherWorkflow",
+					}),
+				},
+			});
+
+			expect(result.workflows).toEqual([
+				{
+					binding: "MY_WORKFLOW",
+					class_name: "MyWorkflow",
+					script_name: "workflow-worker",
+					remote: true,
+				},
+				{
+					binding: "UNTYPED_WORKFLOW",
+					class_name: "OtherWorkflow",
+					script_name: "other-worker",
+				},
+			]);
+		});
+	});
+
 	describe("triggers", () => {
 		it("maps scheduled triggers to triggers.crons", ({ expect }) => {
 			const result = convertToWranglerConfig({

packages/config/src/__tests__/schema.test.ts

@@ -237,6 +237,48 @@ describe("InputWorkerSchema", () => {
 		});
 	});
 
+	describe("Workflows", () => {
+		it("accepts Workflow exports and bindings", ({ expect }) => {
+			const result = InputWorkerSchema.safeParse({
+				...baseConfig,
+				env: {
+					MY_WORKFLOW: {
+						type: "workflow",
+						workerName: "workflow-worker",
+						exportName: "MyWorkflow",
+						remote: true,
+					},
+				},
+				exports: {
+					MyWorkflow: {
+						type: "workflow",
+						name: "my-workflow",
+						limits: { steps: 25_000 },
+						schedules: ["0 * * * *"],
+					},
+				},
+			});
+
+			expect(result.success).toBe(true);
+		});
+
+		it("rejects invalid Workflow export configuration", ({ expect }) => {
+			const result = InputWorkerSchema.safeParse({
+				...baseConfig,
+				exports: {
+					MyWorkflow: {
+						type: "workflow",
+						name: "",
+						limits: { steps: 25_001 },
+						schedules: [],
+					},
+				},
+			});
+
+			expect(result.success).toBe(false);
+		});
+	});
+
 	describe("unknown property rejection", () => {
 		it("rejects unknown top-level keys (typo)", ({ expect }) => {
 			const result = InputWorkerSchema.safeParse({

packages/config/src/bindings.ts

@@ -828,13 +828,12 @@ export interface Bindings {
 	worker(options: WorkerBindingOptions): WorkerBinding;
 	/** Binding to a Worker Loader. */
 	workerLoader(): WorkerLoaderBinding;
-	// TODO: re-enable when workflow bindings return.
-	// /**
-	//  * Create a Workflow binding.
-	//  * `workerName` must match a known config's name (or any `string` for untyped bindings).
-	//  * `exportName` must be a valid `WorkflowEntrypoint` export for the given Worker.
-	//  */
-	// workflow(options: WorkflowBindingOptions): WorkflowBinding;
+	/**
+	 * Create a Workflow binding.
+	 * `workerName` must match a known config's name (or any `string` for untyped bindings).
+	 * `exportName` must be a valid `WorkflowEntrypoint` export for the given Worker.
+	 */
+	workflow(options: WorkflowBindingOptions): WorkflowBinding;
 }
 
 export const bindings = {
@@ -885,6 +884,5 @@ export const bindings = {
 	webSearch: (options) => ({ type: "web-search", ...options }),
 	worker: (options) => ({ type: "worker", ...options }),
 	workerLoader: () => ({ type: "worker-loader" }),
-	// TODO: re-enable when workflow bindings return.
-	// workflow: (options) => ({ type: "workflow", ...options }),
+	workflow: (options) => ({ type: "workflow", ...options }),
 } as Bindings;

packages/config/src/convert.ts

@@ -543,18 +543,17 @@ function convertBindingsAndAssets(
 				workerLoaders.push({ binding: name });
 				break;
 			}
-			// TODO: re-enable when workflow bindings return.
-			// case "workflow": {
-			// 	workflows.push(
-			// 		omitUndefined({
-			// 			binding: name,
-			// 			class_name: binding.exportName,
-			// 			script_name: binding.workerName,
-			// 			remote: binding.remote,
-			// 		})
-			// 	);
-			// 	break;
-			// }
+			case "workflow": {
+				workflows.push(
+					omitUndefined({
+						binding: name,
+						class_name: binding.exportName,
+						script_name: binding.workerName,
+						remote: binding.remote,
+					})
+				);
+				break;
+			}
 		}
 	}
 
@@ -683,6 +682,10 @@ function convertExports(
 			converted[exportName] = value;
 			continue;
 		}
+		if (value.type === "workflow") {
+			converted[exportName] = value;
+			continue;
+		}
 
 		if (value.type !== "durable-object") {
 			unknownExports[exportName] = value;

packages/config/src/exports.ts

@@ -125,6 +125,23 @@ export interface WorkerEntrypointExport extends WorkerEntrypointExportOptions {
 	type: "worker";
 }
 
+export interface WorkflowExportOptions {
+	/** The account-unique name of the Workflow. */
+	name: string;
+	/** Optional limits for the Workflow. */
+	limits?: {
+		/** Maximum number of steps a Workflow instance can execute. */
+		steps?: number;
+	};
+	/** Optional cron schedules for automatically triggering Workflow instances. */
+	schedules?: string[];
+}
+
+/** Declares a Workflow defined by this Worker. */
+export interface WorkflowExport extends WorkflowExportOptions {
+	type: "workflow";
+}
+
 /**
  * Configuration for named exports declared by the Worker. Each entry's
  * key is the exported class name; the value configures the export.
@@ -179,6 +196,9 @@ export interface Exports {
 
 	/** Declares a WorkerEntrypoint export defined by this Worker. */
 	worker(options?: WorkerEntrypointExportOptions): WorkerEntrypointExport;
+
+	/** Declares a WorkflowEntrypoint export defined by this Worker. */
+	workflow(options: WorkflowExportOptions): WorkflowExport;
 }
 
 function durableObject(
@@ -213,6 +233,10 @@ function worker(
 	return { type: "worker", ...options };
 }
 
+function workflow(options: WorkflowExportOptions): WorkflowExport {
+	return { type: "workflow", ...options };
+}
+
 /**
  * Exports builder for configuring Worker exports.
  *
@@ -234,4 +258,5 @@ function worker(
 export const exports: Exports = {
 	durableObject,
 	worker,
+	workflow,
 };

packages/config/src/public.ts

@@ -67,6 +67,8 @@ export type {
 	DurableObjectExpectingTransferExport,
 	WorkerEntrypointExport,
 	WorkerEntrypointExportOptions,
+	WorkflowExport,
+	WorkflowExportOptions,
 } from "./exports";
 export { exports } from "./exports";
 export type {

packages/config/src/schema.ts

@@ -186,13 +186,12 @@ const KnownBindingSchema = z.discriminatedUnion("type", [
 		remote: z.boolean().optional(),
 	}),
 	z.strictObject({ type: z.literal("worker-loader") }),
-	// TODO: support Workflows
-	// z.strictObject({
-	// 	type: z.literal("workflow"),
-	// 	workerName: z.string(),
-	// 	exportName: z.string(),
-	// 	remote: z.boolean().optional(),
-	// }),
+	z.strictObject({
+		type: z.literal("workflow"),
+		workerName: z.string(),
+		exportName: z.string(),
+		remote: z.boolean().optional(),
+	}),
 ]);
 
 const UnsafeBindingSchema = z.looseObject({
@@ -321,12 +320,14 @@ const ExportSchema = z.union([
 		type: z.literal("worker"),
 		cache: z.strictObject({ enabled: z.boolean() }).optional(),
 	}),
-	// TODO: support Workflows
-	// z.strictObject({
-	// 	type: z.literal("workflow"),
-	// 	name: z.string(),
-	// 	limits: z.strictObject({ steps: z.number().optional() }).optional(),
-	// }),
+	z.strictObject({
+		type: z.literal("workflow"),
+		name: z.string().min(1),
+		limits: z
+			.strictObject({ steps: z.number().int().min(1).max(25_000).optional() })
+			.optional(),
+		schedules: z.array(z.string().min(1)).min(1).max(100).optional(),
+	}),
 ]);
 
 const LimitsSchema = z.strictObject({

packages/config/src/types.ts

@@ -43,8 +43,7 @@ import type {
 	WebSearchBinding,
 	WorkerBinding,
 	WorkerLoaderBinding,
-	// TODO: re-enable when workflow bindings return.
-	// WorkflowBinding,
+	WorkflowBinding,
 } from "./bindings";
 import type {
 	DurableObjectDeletedExport,
@@ -53,6 +52,7 @@ import type {
 	DurableObjectRenamedExport,
 	DurableObjectTransferredExport,
 	WorkerEntrypointExport,
+	WorkflowExport,
 } from "./exports";
 import type { WorkerModule } from "./inference";
 import type {
@@ -100,9 +100,8 @@ type Binding =
 	| VpcServiceBinding
 	| WebSearchBinding
 	| WorkerBinding
-	| WorkerLoaderBinding;
-// TODO: re-enable when workflow bindings return.
-// | WorkflowBinding;
+	| WorkerLoaderBinding
+	| WorkflowBinding;
 
 /**
  * Union of all trigger definitions accepted in `triggers`.
@@ -120,8 +119,8 @@ type Export =
 	| DurableObjectRenamedExport
 	| DurableObjectTransferredExport
 	| DurableObjectExpectingTransferExport
-	| WorkerEntrypointExport;
-// TODO: support Workflows
+	| WorkerEntrypointExport
+	| WorkflowExport;
 
 /**
  * Worker configuration. This is the input shape passed to