diff --git a/src/locutus.ts b/src/locutus.ts
index 58a5cc1..f92f8dd 100644
--- a/src/locutus.ts
+++ b/src/locutus.ts
@@ -100,7 +100,8 @@ export class App {
             this.defaultLocation = "/";
             this.setHash("/");
         } else {
-            throw Error(response.message);
+            console.error(response.error);
+            throw Error(response.error.message || response.error.code);
         }
     }
 
@@ -237,14 +238,14 @@ export class App {
                 this.addMessage(input.value);
                 const val = input.value;
                 input.value = "";
-                await this.session.sendEvent("60nc0XXDIYUh6QzX4p0rMpCdzDmxghZLZk8dLuQh628", {
+                await this.session.newEvent("60nc0XXDIYUh6QzX4p0rMpCdzDmxghZLZk8dLuQh628", {
                     message: val,
                 });
             }
         });
 
         this.session.subscribe(response => {
-            this.addMessage(response.data.event.data.message);
+            this.addMessage(response.data.data.message);
         });
     }
 }
diff --git a/src/usimp.ts b/src/usimp.ts
index e25b5e6..d2105f7 100644
--- a/src/usimp.ts
+++ b/src/usimp.ts
@@ -19,12 +19,15 @@ interface DomainServerJson {
     }
 }
 
-interface EventJson {
-    data: {
-        event: {
-            data: any
-        }
-    }
+interface OutputEnvelopeJson {
+    status: string,
+    request_nr: number,
+    data: any,
+    error: {
+        code: string,
+        message: string | null,
+        description: string | null,
+    } | null,
 }
 
 interface WellKnownJson {
@@ -145,6 +148,7 @@ export class Session {
     httpBaseUrl: string | null;
     websocket: WebSocket | null;
     numRequests: number;
+    subscriptions: string[];
 
     constructor(domain: Domain) {
         this.domain = domain;
@@ -153,6 +157,7 @@ export class Session {
         this.token = null;
         this.httpBaseUrl = null;
         this.websocket = null;
+        this.subscriptions = [];
     }
 
     async chooseDomainServer(): Promise<{ http: number | null, ws: number | null } | undefined> {
@@ -238,28 +243,43 @@ export class Session {
         });
     }
 
-    async send(endpoint: string, data: object, timeout: number = 2000, forceHttp: boolean = false) {
+    async send(endpoint: string, data: any, timeout: number = 2000, forceHttp: boolean = false, cb: ((a: OutputEnvelopeJson) => void) | null = null) {
         this.numRequests++;
-
         while (true) {
             try {
-                if (!forceHttp && this.websocket) {
+                if (!forceHttp && this.websocket !== null) {
                     const req_nr = this.numRequests;
-                    const response = this.waitForWebSocketResponse(req_nr, timeout);
-
                     const startTime = performance.now();
+
+                    let response;
+                    if (cb === null) {
+                        response = this.waitForWebSocketResponse(req_nr, timeout);
+                    } else {
+                        this.websocket.addEventListener("message", (msg) => {
+                            const data = JSON.parse(msg.data);
+                            if (data['request_nr'] === req_nr) {
+                                cb(data);
+                            }
+                        });
+                    }
+
                     await this.waitForWebSocket();
                     await this.websocket.send(JSON.stringify({
                         'request_nr': req_nr,
                         'endpoint': endpoint,
                         'to_domain': this.domain.id,
+                        'token': this.token,
                         'data': data
                     }));
-                    const responseData = await response;
 
-                    const endTime = performance.now();
-                    responseData.duration = endTime - startTime;
-                    return responseData;
+                    if (cb === null) {
+                        const responseData = await response;
+                        const endTime = performance.now();
+                        responseData.duration = endTime - startTime;
+                        return responseData;
+                    } else {
+                        return null;  // TODO subscription id
+                    }
                 } else {
                     const controller = new AbortController();
                     const timer = setTimeout(() => controller.abort(), timeout);
@@ -322,46 +342,37 @@ export class Session {
         return response;
     }
 
-    async sendEvent(roomId: string, data: object) {
-        return this.send("send_event", {
+    async newEvent(roomId: string, data: any) {
+        return this.send("new_event", {
             room_id: roomId,
-            data: data,
+            events: [{
+                data: data
+            }],
         });
     }
 
-    subscribe(func: (a: EventJson) => void) {
+    async subscribe(cb: (a: OutputEnvelopeJson) => void) {
         this.numRequests++;
-        if (this.websocket) {
-            // TODO
+        if (this.websocket !== null) {
+            let subscription = await this.send('subscribe', {}, 60_000, false, cb);
+            this.subscriptions.push(subscription);
+            return subscription;
         } else {
-            let headers: Record<string, string> = {
-                'Content-Type': 'application/json',
-                'To-Domain': this.domain.id,
-            };
-            if (this.token) {
-                headers['Authorization'] = `usimp ${this.token}`;
-            }
-
-            fetch(`${this.httpBaseUrl}/subscribe`, {
-                method: "POST",
-                headers: headers,
-                body: JSON.stringify({}),
-            }).then(response => {
-                return response.json();
-            }).then(response => {
-                if (response.status === "success") {
-                    this.subscribe(func);
-                    func(response);
+            this.send('subscribe', {}, 60_000).then((res) => {
+                if (res.status === "success") {
+                    this.subscribe(cb);
+                    cb(res);
                 } else {
                     setTimeout(() => {
-                        this.subscribe(func);
+                        this.subscribe(cb);
                     }, 1000);
                 }
             }).catch(() => {
                 setTimeout(() => {
-                    this.subscribe(func);
+                    this.subscribe(cb);
                 }, 1000);
             });
+            return null;  // TODO subscription id
         }
     }
 }