diff --git a/domain/resmon.js b/domain/resmon.js
index 51f1a11..f1ea0c1 100644
--- a/domain/resmon.js
+++ b/domain/resmon.js
@@ -9,14 +9,13 @@
 
   start() {
     const { interval } = application.resmon.config;
-    setInterval(() => {
+    setTimeout(() => {
       const stats = application.resmon.getStatistics();
-      const { heapTotal, heapUsed, external, contexts, detached } = stats;
+      const { heapTotal, heapUsed, external } = stats;
       const total = application.utils.bytesToSize(heapTotal);
       const used = application.utils.bytesToSize(heapUsed);
       const ext = application.utils.bytesToSize(external);
       console.log(`Heap: ${used} of ${total}, ext: ${ext}`);
-      console.log(`Contexts: ${contexts}, detached: ${detached}`);
     }, interval);
   }
 });
diff --git a/lib/client.js b/lib/client.js
index 058dac4..55eefa7 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -50,13 +50,15 @@ class Client {
     res.end();
   }
 
-  error(status, err) {
+  error(status, err, callId = err) {
     const { req: { url }, res, connection } = this;
     const reason = http.STATUS_CODES[status];
+    if (typeof err === 'number') err = undefined;
     const error = err ? err.stack : reason;
     const msg = status === 403 ? err.message : `${url} - ${error} - ${status}`;
     application.logger.error(msg);
-    const result = JSON.stringify({ result: 'error', reason });
+    const packet = { callback: callId, error: { message: reason } };
+    const result = JSON.stringify(packet);
     if (connection) {
       connection.send(result);
       return;
@@ -66,24 +68,32 @@ class Client {
     res.end(result);
   }
 
-  async rpc(method, args) {
+  message(data) {
+    const packet = JSON.parse(data);
+    const [callType, methodName] = Object.keys(packet);
+    const callId = packet[callType];
+    const args = packet[methodName];
+    this.rpc(callId, methodName, args);
+  }
+
+  async rpc(callId, method, args) {
     const { res, connection } = this;
     const { semaphore } = application.server;
     try {
       await semaphore.enter();
     } catch {
-      this.error(504);
+      this.error(504, callId);
       return;
     }
     try {
       const session = await application.auth.restore(this);
       const proc = application.runMethod(method, session);
       if (!proc) {
-        this.error(404);
+        this.error(404, callId);
         return;
       }
       if (!session && proc.access !== 'public') {
-        this.error(403, new Error(`Forbidden: /api/${method}`));
+        this.error(403, new Error(`Forbidden: /api/${method}`), callId);
         return;
       }
       const result = await proc.method(args);
@@ -91,11 +101,12 @@ class Client {
         const session = application.auth.start(this, result.userId);
         result.token = session.token;
       }
-      const data = JSON.stringify(result);
+      const packet = { callback: callId, result };
+      const data = JSON.stringify(packet);
       if (connection) connection.send(data);
       else res.end(data);
     } catch (err) {
-      this.error(500, err);
+      this.error(500, err, callId);
     } finally {
       semaphore.leave();
     }
diff --git a/lib/server.js b/lib/server.js
index 48fb33a..41be437 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -9,7 +9,6 @@ const Client = require('./client.js');
 
 const SHUTDOWN_TIMEOUT = 5000;
 const LONG_RESPONSE = 30000;
-const METHOD_OFFSET = '/api/'.length;
 
 const clients = new Map();
 
@@ -51,15 +50,13 @@ const listener = (req, res) => {
   });
 
   application.logger.log(`${method}\t${url}`);
-  if (url.startsWith('/api/')) {
+  if (url === '/api') {
     if (method !== 'POST') {
       client.error(403, new Error(`Forbidden: ${url}`));
       return;
     }
-    receiveBody(req).then(body => {
-      const method = url.substring(METHOD_OFFSET);
-      const args = JSON.parse(body);
-      client.rpc(method, args);
+    receiveBody(req).then(data => {
+      client.message(data);
     });
   } else {
     if (url === '/' && !req.connection.encrypted) {
@@ -84,9 +81,8 @@ class Server {
     this.ws = new WebSocket.Server({ server: this.instance });
     this.ws.on('connection', (connection, req) => {
       const client = new Client(req, null, connection);
-      connection.on('message', message => {
-        const { method, args } = JSON.parse(message);
-        client.rpc(method, args);
+      connection.on('message', data => {
+        client.message(data);
       });
     });
     this.instance.listen(port, host);
diff --git a/static/.eslintrc.json b/static/.eslintrc.json
new file mode 100644
index 0000000..bd14a19
--- /dev/null
+++ b/static/.eslintrc.json
@@ -0,0 +1,5 @@
+{
+  "parserOptions": {
+    "sourceType": "module"
+  }
+}
diff --git a/static/console.js b/static/console.js
index f561a11..11cc39a 100644
--- a/static/console.js
+++ b/static/console.js
@@ -1,39 +1,8 @@
-'use strict';
+import { Metacom } from './metacom.js';
 
-// API Builder
-
-const socket = new WebSocket('wss://' + location.host);
-
-const buildAPI = (methods, socket = null) => {
-  const api = {};
-  for (const method of methods) {
-    api[method] = (args = {}) => new Promise((resolve, reject) => {
-      if (socket) {
-        socket.send(JSON.stringify({ method, args }));
-        socket.onmessage = event => {
-          const obj = JSON.parse(event.data);
-          if (obj.result !== 'error') resolve(obj);
-          else reject(new Error(`Status Code: ${obj.reason}`));
-        };
-      } else {
-        fetch(`/api/${method}`, {
-          method: 'POST',
-          headers: { 'Content-Type': 'application/json' },
-          body: JSON.stringify(args),
-        }).then(res => {
-          const { status } = res;
-          if (status === 200) resolve(res.json());
-          else reject(new Error(`Status Code: ${status}`));
-        });
-      }
-    });
-  }
-  return api;
-};
-
-let api = buildAPI(['status', 'signIn', 'introspection'], socket);
-
-// Console Emulation
+const metacom = new Metacom(location.host);
+const { api } = metacom;
+window.api = api;
 
 const ALPHA_UPPER = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
 const ALPHA_LOWER = 'abcdefghijklmnopqrstuvwxyz';
@@ -276,12 +245,12 @@ function commandLoop() {
 
 const signIn = async () => {
   try {
+    await metacom.load('status', 'signIn', 'introspection');
     await api.status();
   } catch (err) {
     await api.signIn({ login: 'marcus', password: 'marcus' });
   }
-  const methods = await api.introspection();
-  api = buildAPI(methods, socket);
+  await metacom.load('example');
 };
 
 window.addEventListener('load', () => {
diff --git a/static/index.html b/static/index.html
index 6be5c1b..595ef62 100644
--- a/static/index.html
+++ b/static/index.html
@@ -5,7 +5,7 @@
     <meta charset="utf-8">
     <link rel="manifest" href="/manifest.json">
     <link rel="stylesheet" href="/console.css">
-    <script src="console.js"></script>
+    <script src="console.js" type="module"></script>
     <meta name="HandheldFriendly" content="true" />
     <meta name="apple-mobile-web-app-capable" content="yes" />
     <meta name="apple-mobile-web-app-status-bar-style" content="black" />
diff --git a/static/metacom.js b/static/metacom.js
new file mode 100644
index 0000000..afc5807
--- /dev/null
+++ b/static/metacom.js
@@ -0,0 +1,59 @@
+export class Metacom {
+  constructor(host) {
+    this.socket = new WebSocket('wss://' + host);
+    this.api = {};
+    this.callId = 0;
+    this.calls = new Map();
+    this.socket.onmessage = ({ data }) => {
+      try {
+        const packet = JSON.parse(data);
+        const { callback, event } = packet;
+        const callId = callback || event;
+        const [resolve, reject] = this.calls.get(callId);
+        if (packet.error) {
+          const { code, message } = packet.error;
+          const error = new Error(message);
+          error.code = code;
+          reject(error);
+          return;
+        }
+        resolve(packet.result);
+      } catch (err) {
+        console.error(err);
+      }
+    };
+  }
+
+  async load(...methods) {
+    for (const methodName of methods) {
+      this.api[methodName] = this.socketCall(methodName);
+    }
+  }
+
+  httpCall(methodName) {
+    return (args = {}) => {
+      const callId = ++this.callId;
+      const packet = { call: callId, [methodName]: args };
+      return fetch('/api', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify(packet),
+      }).then(res => {
+        const { status } = res;
+        if (status === 200) return res.json().then(({ result }) => result);
+        throw new Error(`Status Code: ${status}`);
+      });
+    };
+  }
+
+  socketCall(methodName) {
+    return (args = {}) => {
+      const callId = ++this.callId;
+      return new Promise((resolve, reject) => {
+        this.calls.set(callId, [resolve, reject]);
+        const packet = { call: callId, [methodName]: args };
+        this.socket.send(JSON.stringify(packet));
+      });
+    };
+  }
+}
diff --git a/test/system.js b/test/system.js
index 9955cc4..fffec46 100644
--- a/test/system.js
+++ b/test/system.js
@@ -11,6 +11,8 @@ const PORT = 8000;
 const START_TIMEOUT = 1000;
 const TEST_TIMEOUT = 3000;
 
+let callId = 0;
+
 console.log('System test started');
 setTimeout(async () => {
   worker.postMessage({ name: 'stop' });
@@ -24,8 +26,9 @@ const tasks = [
   { get: '/', status: 302 },
   { get: '/console.js' },
   {
-    post: '/api/signIn',
-    data: { login: 'marcus', password: 'marcus' }
+    post: '/api',
+    method: 'signIn',
+    args: { login: 'marcus', password: 'marcus' }
   }
 ];
 
@@ -42,8 +45,9 @@ const getRequest = task => {
     request.method = 'POST';
     request.path = task.post;
   }
-  if (task.data) {
-    task.data = JSON.stringify(task.data);
+  if (task.args) {
+    const packet = { call: ++callId, [task.method]: task.args };
+    task.data = JSON.stringify(packet);
     request.headers = {
       'Content-Type': 'application/json',
       'Content-Length': task.data.length