feat(cloudflare): bind Workflows to async Workers

packages/alchemy/src/Cloudflare/Workers/InferEnv.ts

@@ -4,6 +4,7 @@ import type * as Effect from "effect/Effect";
 import type { Redacted } from "effect/Redacted";
 import type * as Stream from "effect/Stream";
 import type { Rpc } from "../../Rpc.ts";
+import type { WorkflowLike } from "../Workflows/Workflow.ts";
 // NOTE: import the service modules directly rather than `import * as Cloudflare
 // from "../index.ts"`. Importing the whole Cloudflare barrel here creates a
 // circular re-export when the barrel does `export * from "./Workers/index.ts"`
@@ -79,15 +80,17 @@ export type GetBindingType<T> =
                                         ? WorkerVersionMetadata
                                         : T extends WorkerLoaderResource
                                           ? WorkerLoader
-                                          : T extends DurableObjectLike
-                                            ? DurableObjectNamespace<
-                                                Exclude<T["Shape"], undefined>
-                                              >
-                                            : T extends Redacted<any>
-                                              ? // redacteds are always stored as secret_text, so are always string
-                                                // we JSON.stringify when not a Redacted<string>
-                                                string
-                                              : T;
+                                          : T extends WorkflowLike<infer Params>
+                                            ? Workflow<Params>
+                                            : T extends DurableObjectLike
+                                              ? DurableObjectNamespace<
+                                                  Exclude<T["Shape"], undefined>
+                                                >
+                                              : T extends Redacted<any>
+                                                ? // redacteds are always stored as secret_text, so are always string
+                                                  // we JSON.stringify when not a Redacted<string>
+                                                  string
+                                                : T;
 
 /**
  * Cloudflare service-binding wire shape for an Effect-native Worker.

packages/alchemy/src/Cloudflare/Workers/WorkerAsyncBindings.ts

@@ -21,6 +21,7 @@ import { isQueue } from "../Queues/Queue.ts";
 import { isBucket } from "../R2/Bucket.ts";
 import { isSecret } from "../SecretsStore/Secret.ts";
 import { isIndex } from "../Vectorize/VectorizeIndex.ts";
+import { isWorkflowLike, WorkflowResource } from "../Workflows/Workflow.ts";
 import { isAssets } from "./Assets.ts";
 import { isBrowser } from "./Browser.ts";
 import { isDurableObjectLike } from "./DurableObject.ts";
@@ -64,6 +65,20 @@ export const bindWorkerAsyncBindings = Effect.fn(function* (
             ? getHyperdriveDevOrigin(binding)
             : undefined,
         });
+
+        // A locally-hosted Workflow (no `scriptName`) must be registered with
+        // Cloudflare via `putWorkflow` once the host Worker exists. Cross-script
+        // references (with `scriptName`) are reference-only — the host owns the
+        // workflow resource. `scriptName: resource.workerName` makes the
+        // WorkflowResource depend on the Worker so it reconciles afterwards.
+        if (isWorkflowLike(binding) && !binding.scriptName) {
+          const workflowName = binding.workflowName ?? binding.name;
+          yield* WorkflowResource(workflowName, {
+            workflowName,
+            className: binding.className ?? binding.name,
+            scriptName: resource.workerName,
+          });
+        }
       } else {
         return yield* Effect.die(`Unknown binding type: ${bindingName}`);
       }
@@ -155,6 +170,14 @@ const toBinding = (
       className: binding.className ?? binding.name,
       scriptName: binding.scriptName,
     };
+  } else if (isWorkflowLike(binding)) {
+    return {
+      type: "workflow",
+      name: bindingName,
+      workflowName: binding.workflowName ?? binding.name,
+      className: binding.className ?? binding.name,
+      scriptName: binding.scriptName,
+    };
   } else if (isDatabase(binding)) {
     return {
       type: "d1",

packages/alchemy/src/Cloudflare/Workers/WorkerBinding.ts

@@ -20,6 +20,7 @@ import type { Queue } from "../Queues/Queue.ts";
 import type { Bucket } from "../R2/Bucket.ts";
 import type { Secret } from "../SecretsStore/Secret.ts";
 import type { Index as VectorizeIndex } from "../Vectorize/VectorizeIndex.ts";
+import type { WorkflowLike } from "../Workflows/Workflow.ts";
 import type { Assets } from "./Assets.ts";
 import type { BrowserBinding } from "./BrowserBinding.ts";
 import type { DurableObjectLike } from "./DurableObject.ts";
@@ -66,7 +67,8 @@ export type WorkerBindingResource =
   | Worker
   | WorkerLoader
   | VersionMetadataBinding
-  | DurableObjectLike<any>;
+  | DurableObjectLike<any>
+  | WorkflowLike<any>;
 
 export type WorkerBindings = {
   [bindingName in string]: WorkerBindingResource;