diff --git a/__tests__/typescript-stress.test.ts b/__tests__/typescript-stress.test.ts
index 7ae62469..27eb8f23 100644
--- a/__tests__/typescript-stress.test.ts
+++ b/__tests__/typescript-stress.test.ts
@@ -77,7 +77,7 @@ export class MockTransport extends Transport {
     super(NaiveJsonCodec, clientId);
   }
 
-  send(msg: OpaqueTransportMessage): MessageId {
+  async send(msg: OpaqueTransportMessage): Promise<MessageId> {
     const id = msg.id;
     return id;
   }
diff --git a/index.ts b/index.ts
index 8f5563db..ec49013b 100644
--- a/index.ts
+++ b/index.ts
@@ -43,6 +43,5 @@ export {
   onServerReady,
   createWsTransports,
   waitForMessage,
-  waitForSocketReady,
-  createWebSocketClient,
+  createLocalWebSocketClient,
 } from './transport/util';
diff --git a/package-lock.json b/package-lock.json
index 5e8feec1..5c49cff6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@replit/river",
-  "version": "0.1.10",
+  "version": "0.2.0",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "@replit/river",
-      "version": "0.1.10",
+      "version": "0.2.0",
       "license": "MIT",
       "dependencies": {
         "@sinclair/typebox": "^0.31.8",
diff --git a/package.json b/package.json
index 99fa708b..c9481009 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "name": "@replit/river",
   "sideEffects": false,
   "description": "It's like tRPC but... with JSON Schema Support, duplex streaming and support for service multiplexing. Transport agnostic!",
-  "version": "0.1.10",
+  "version": "0.2.0",
   "type": "module",
   "main": "index.js",
   "types": "index.d.ts",
diff --git a/router/client.ts b/router/client.ts
index 3dccce49..57fb9282 100644
--- a/router/client.ts
+++ b/router/client.ts
@@ -74,7 +74,7 @@ export const createClient = <Srv extends Server<Record<string, AnyService>>>(
       // this gets cleaned up on i.end() which is called by closeHandler
       (async () => {
         for await (const rawIn of i) {
-          transport.send(
+          await transport.send(
             msg(
               transport.clientId,
               'SERVER',
@@ -103,7 +103,7 @@ export const createClient = <Srv extends Server<Record<string, AnyService>>>(
       return [i, o, closeHandler];
     } else {
       // rpc case
-      const id = transport.send(
+      const id = await transport.send(
         msg(
           transport.clientId,
           'SERVER',
diff --git a/router/server.ts b/router/server.ts
index 85512649..7033b97f 100644
--- a/router/server.ts
+++ b/router/server.ts
@@ -63,7 +63,7 @@ export async function createServer<Services extends Record<string, AnyService>>(
             // sending outgoing messages back to client
             (async () => {
               for await (const response of outgoing) {
-                transport.send(response);
+                await transport.send(response);
               }
             })(),
           ]),
@@ -101,7 +101,7 @@ export async function createServer<Services extends Record<string, AnyService>>(
             getContext(service),
             inputMessage,
           );
-          transport.send(response);
+          await transport.send(response);
           return;
         } else if (
           procedure.type === 'stream' &&
diff --git a/transport/message.ts b/transport/message.ts
index 59deea40..80bf324f 100644
--- a/transport/message.ts
+++ b/transport/message.ts
@@ -32,6 +32,7 @@ export type MessageId = string;
 export type OpaqueTransportMessage = TransportMessage<unknown>;
 export type TransportClientId = 'SERVER' | string;
 export const TransportAckSchema = Type.Object({
+  id: Type.String(),
   from: Type.String(),
   ack: Type.String(),
 });
@@ -63,6 +64,7 @@ export function payloadToTransportMessage<Payload extends object>(
 
 export function ack(msg: OpaqueTransportMessage): TransportMessageAck {
   return {
+    id: nanoid(),
     from: msg.to,
     ack: msg.id,
   };
diff --git a/transport/stream.test.ts b/transport/stream.test.ts
index 74219f3b..563d629b 100644
--- a/transport/stream.test.ts
+++ b/transport/stream.test.ts
@@ -24,7 +24,7 @@ describe('sending and receiving across node streams works', () => {
     };
 
     const p = waitForMessage(serverTransport);
-    clientTransport.send({
+    await clientTransport.send({
       id: '1',
       from: 'client',
       to: 'SERVER',
diff --git a/transport/stream.ts b/transport/stream.ts
index de7ee142..a30f0cb8 100644
--- a/transport/stream.ts
+++ b/transport/stream.ts
@@ -22,7 +22,7 @@ export class StreamTransport extends Transport {
     rl.on('line', (msg) => this.onMessage(msg));
   }
 
-  send(msg: OpaqueTransportMessage): string {
+  async send(msg: OpaqueTransportMessage): Promise<string> {
     const id = msg.id;
     this.output.write(this.codec.toStringBuf(msg) + '\n');
     return id;
diff --git a/transport/types.ts b/transport/types.ts
index 3fd36244..d8ecedea 100644
--- a/transport/types.ts
+++ b/transport/types.ts
@@ -53,6 +53,8 @@ export abstract class Transport {
     this.handlers.delete(handler);
   }
 
-  abstract send(msg: OpaqueTransportMessage | TransportMessageAck): MessageId;
+  abstract send(
+    msg: OpaqueTransportMessage | TransportMessageAck,
+  ): Promise<MessageId>;
   abstract close(): Promise<void>;
 }
diff --git a/transport/util.ts b/transport/util.ts
index be3a0734..8ea38a7a 100644
--- a/transport/util.ts
+++ b/transport/util.ts
@@ -18,33 +18,25 @@ export async function onServerReady(
   });
 }
 
+export async function createLocalWebSocketClient(port: number) {
+  return new WebSocket(`ws://localhost:${port}`);
+}
+
 export async function createWsTransports(
   port: number,
   wss: WebSocketServer,
 ): Promise<[Transport, Transport]> {
   return new Promise((resolve) => {
-    const clientSockPromise = createWebSocketClient(port);
+    const clientSockPromise = createLocalWebSocketClient(port);
     wss.on('connection', async (serverSock) => {
       resolve([
-        new WebSocketTransport(await clientSockPromise, 'client'),
-        new WebSocketTransport(serverSock, 'SERVER'),
+        new WebSocketTransport(() => clientSockPromise, 'client'),
+        new WebSocketTransport(() => Promise.resolve(serverSock), 'SERVER'),
       ]);
     });
   });
 }
 
-export async function waitForSocketReady(socket: WebSocket) {
-  return new Promise<void>((resolve) => {
-    socket.addEventListener('open', () => resolve());
-  });
-}
-
-export async function createWebSocketClient(port: number) {
-  const client = new WebSocket(`ws://localhost:${port}`);
-  await waitForSocketReady(client);
-  return client;
-}
-
 export async function waitForMessage(
   t: Transport,
   filter?: (msg: OpaqueTransportMessage) => boolean,
diff --git a/transport/ws.test.ts b/transport/ws.test.ts
index 1418f036..67de7a4a 100644
--- a/transport/ws.test.ts
+++ b/transport/ws.test.ts
@@ -3,7 +3,7 @@ import { WebSocketServer } from 'ws';
 import { WebSocketTransport } from './ws';
 import { describe, test, expect, beforeAll, afterAll } from 'vitest';
 import {
-  createWebSocketClient,
+  createLocalWebSocketClient,
   createWebSocketServer,
   onServerReady,
   waitForMessage,
@@ -28,18 +28,22 @@ describe('sending and receiving across websockets works', () => {
   test('basic send/receive', async () => {
     let serverTransport: WebSocketTransport | undefined;
     wss.on('connection', (conn) => {
-      serverTransport = new WebSocketTransport(conn, 'SERVER');
+      serverTransport = new WebSocketTransport(
+        () => Promise.resolve(conn),
+        'SERVER',
+      );
     });
-
-    const clientSoc = await createWebSocketClient(port);
-    const clientTransport = new WebSocketTransport(clientSoc, 'client');
+    const clientTransport = new WebSocketTransport(
+      () => createLocalWebSocketClient(port),
+      'client',
+    );
 
     const msg = {
       msg: 'cool',
       test: 123,
     };
 
-    clientTransport.send({
+    await clientTransport.send({
       id: '1',
       from: 'client',
       to: 'SERVER',
diff --git a/transport/ws.ts b/transport/ws.ts
index a6433311..04a58a4b 100644
--- a/transport/ws.ts
+++ b/transport/ws.ts
@@ -1,4 +1,4 @@
-import type WebSocket from 'isomorphic-ws';
+import WebSocket from 'isomorphic-ws';
 import { Transport } from './types';
 import { NaiveJsonCodec } from '../codec/json';
 import {
@@ -13,21 +13,60 @@ import {
 // - how do we handle forceful client disconnects? (i.e. broken connection, offline)
 // - how do we handle forceful service disconnects (i.e. a crash)?
 export class WebSocketTransport extends Transport {
-  ws: WebSocket;
+  wsGetter: () => Promise<WebSocket>;
+  ws?: WebSocket;
+  destroyed: boolean;
 
-  constructor(ws: WebSocket, clientId: TransportClientId) {
+  constructor(wsGetter: () => Promise<WebSocket>, clientId: TransportClientId) {
     super(NaiveJsonCodec, clientId);
-    this.ws = ws;
-    ws.onmessage = (msg) => this.onMessage(msg.data.toString());
+    this.destroyed = false;
+    this.wsGetter = wsGetter;
+    this.waitForSocketReady();
   }
 
-  send(msg: OpaqueTransportMessage): MessageId {
+  // postcondition: ws is concretely a WebSocket
+  private async waitForSocketReady(): Promise<WebSocket> {
+    return new Promise<WebSocket>((resolve, reject) => {
+      if (this.destroyed) {
+        reject(new Error('ws is destroyed'));
+        return;
+      }
+
+      if (this.ws) {
+        // constructed ws but not open
+        if (this.ws.readyState === this.ws.OPEN) {
+          return resolve(this.ws);
+        }
+
+        // resolve on open
+        this.ws.onopen = (evt) => {
+          return resolve(evt.target);
+        };
+
+        // reject if borked
+        this.ws.onerror = (err) => reject(err);
+      } else {
+        // not constructed
+        this.wsGetter().then((ws) => {
+          this.ws = ws;
+          return resolve(this.waitForSocketReady());
+        });
+      }
+    }).then((ws) => {
+      ws.onmessage = (msg) => this.onMessage(msg.data.toString());
+      return ws;
+    });
+  }
+
+  async send(msg: OpaqueTransportMessage): Promise<MessageId> {
     const id = msg.id;
-    this.ws.send(this.codec.toStringBuf(msg));
+    const ws = await this.waitForSocketReady();
+    ws.send(this.codec.toStringBuf(msg));
     return id;
   }
 
   async close() {
-    return this.ws.close();
+    this.destroyed = true;
+    return this.ws?.close();
   }
 }