diff --git a/frontend/src/app/app-routing.module.ts b/frontend/src/app/app-routing.module.ts
index 2e4dc0ae..92669888 100644
--- a/frontend/src/app/app-routing.module.ts
+++ b/frontend/src/app/app-routing.module.ts
@@ -16,6 +16,12 @@ const routes: Routes = [
     { path: 'profile', loadChildren: () => import('./profile/profile.module').then((m) => m.ProfileModule) },
   ]),
   Shell.childRoutes([{ path: 'chat', loadChildren: () => import('./chat/chat.module').then((m) => m.ChatModule) }]),
+
+  Shell.childRoutes([{ path: 'chats', loadChildren: () => import('./chat/chat.module').then((m) => m.ChatModule) }]),
+  Shell.childRoutes([
+    { path: 'chats/:id', loadChildren: () => import('./chat/chat.module').then((m) => m.ChatModule) },
+  ]),
+
   Shell.childRoutes([
     {
       path: 'code-reviews',
diff --git a/frontend/src/app/chat/chat.component.html b/frontend/src/app/chat/chat.component.html
index ddb1a3d3..e92e69e9 100644
--- a/frontend/src/app/chat/chat.component.html
+++ b/frontend/src/app/chat/chat.component.html
@@ -1,10 +1,38 @@
-<mat-card>
-  <mat-card-header>
-    <mat-card-title>Chat </mat-card-title>
-  </mat-card-header>
-  <mat-card-content>
-    <ng-container *ngIf="!isLoading"> </ng-container>
+<ng-container *ngIf="chat$ | async as chat">
+  <ng-container *ngIf="true">
+    <!-- auth.user$ | async as user -->
+    <!-- Chat container-->
+    <div fxLayout="column" fxLayoutAlign="center center" style="width: 50%; min-width: 600px; height: 100%">
+      <!-- Header -->
+      <app-chat-header style="width: 100%" [chatId]="chat.id" fxFlex="64px"></app-chat-header>
 
-    <mat-spinner *ngIf="isLoading"></mat-spinner>
-  </mat-card-content>
-</mat-card>
+      <!-- Messages-->
+      <div
+        fxLayout="column"
+        style="
+          width: 100%;
+          overflow-y: scroll;
+          background-color: lightgray;
+          box-shadow: inset 0px 0px 10px rgba(0, 0, 0, 0.5);
+        "
+      >
+        <ng-container *ngFor="let msg of messages; trackBy: trackByCreated; let i = index">
+          <app-chat-message
+            [msg]="msg"
+            [predecessor]="i - 1 >= 0 ? this.messages[i - 1] : null"
+            [user]="user"
+          ></app-chat-message>
+        </ng-container>
+
+        <!-- "is typing" Indicator
+        <app-typing-indicator
+          [user]="user"
+          [typing]="chat.typing"
+        ></app-typing-indicator>-->
+      </div>
+
+      <!-- Send form and other controls -->
+      <app-chat-controls style="width: 100%" [chatId]="chat.id"></app-chat-controls>
+    </div>
+  </ng-container>
+</ng-container>
diff --git a/frontend/src/app/chat/chat.component.scss b/frontend/src/app/chat/chat.component.scss
index e69de29b..5b16a085 100644
--- a/frontend/src/app/chat/chat.component.scss
+++ b/frontend/src/app/chat/chat.component.scss
@@ -0,0 +1,3 @@
+img {
+  border-radius: 50%;
+}
diff --git a/frontend/src/app/chat/chat.component.ts b/frontend/src/app/chat/chat.component.ts
index fda34352..36608644 100644
--- a/frontend/src/app/chat/chat.component.ts
+++ b/frontend/src/app/chat/chat.component.ts
@@ -1,16 +1,65 @@
-import { Component, OnInit } from '@angular/core';
-import { MatDialog } from '@angular/material/dialog';
-import { Router } from '@angular/router';
+import { Component, OnInit, Input } from '@angular/core';
+import { FirebaseChatService } from './services/firebase/firebase-chat.service';
+import { ActivatedRoute } from '@angular/router';
+import { Observable } from 'rxjs';
+import { tap } from 'rxjs/operators';
+// import { FirebaseAuthService } from './services/firebase/firebase-auth.service';
+import { Message } from './model/message';
+import { Chat } from '@app/chat/model/chat';
 
 @Component({
-  selector: 'app-code-review-list',
+  selector: 'app-chat',
   templateUrl: './chat.component.html',
   styleUrls: ['./chat.component.scss'],
 })
 export class ChatComponent implements OnInit {
-  isLoading: boolean = true;
+  @Input() height: string = '';
+  @Input() width: string = '';
 
-  constructor(private router: Router, private dialog: MatDialog) {}
+  user: any = {};
 
-  ngOnInit() {}
+  chat$?: Observable<any>;
+
+  messages: Message[] = [];
+
+  constructor(
+    public chatService: FirebaseChatService,
+    private route: ActivatedRoute
+  ) // public auth: FirebaseAuthService
+  {}
+
+  ngOnInit() {
+    const chatId: string | null = this.route.snapshot.paramMap.get('id');
+    if (!chatId) return;
+    // TODO: first load already existing history
+    // TODO: listen on changes
+    const source = this.chatService.getHistory(chatId);
+    // this.chat$ = this.chatService.buildChat(source).pipe(
+    //   tap(res => this.integrateNewMessages(res)),
+    //   tap(() => this.scrollBottom())
+    // );
+  }
+
+  private integrateNewMessages(chat: Chat) {
+    const newMessages = chat.messages.filter(
+      (newMessage: Message) => !this.messages.some((message: Message) => this.isSameMessage(message, newMessage))
+    );
+    newMessages.forEach((msg) => this.messages.push(msg));
+  }
+
+  private isSameMessage(message: Message, newMessage: Message): boolean {
+    return (
+      message.content === newMessage.content &&
+      message.uid === newMessage.uid &&
+      message.createdAt === newMessage.createdAt
+    );
+  }
+
+  trackByCreated(index: number, msg: Message) {
+    return msg.createdAt;
+  }
+
+  private scrollBottom() {
+    setTimeout(() => window.scrollTo(0, document.body.scrollHeight), 500);
+  }
 }
diff --git a/frontend/src/app/chat/chat.module.ts b/frontend/src/app/chat/chat.module.ts
index 7500c1b9..44414c84 100644
--- a/frontend/src/app/chat/chat.module.ts
+++ b/frontend/src/app/chat/chat.module.ts
@@ -6,9 +6,12 @@ import { FlexLayoutModule } from '@angular/flex-layout';
 import { MaterialModule } from '@app/material.module';
 import { ChatRoutingModule } from '@app/chat/chat-routing.module';
 import { ChatComponent } from '@app/chat/chat.component';
+import { ChatControlsComponent } from '@app/chat/chat-controls/chat-controls.component';
+import { ChatMessageComponent } from '@app/chat/chat-message/chat-message.component';
+import { ChatHeaderComponent } from '@app/chat/chat-header/chat-header.component';
 
 @NgModule({
   imports: [CommonModule, TranslateModule, FlexLayoutModule, MaterialModule, ChatRoutingModule],
-  declarations: [ChatComponent],
+  declarations: [ChatComponent, ChatControlsComponent, ChatMessageComponent, ChatHeaderComponent],
 })
 export class ChatModule {}
diff --git a/frontend/src/app/chat/model/chat.ts b/frontend/src/app/chat/model/chat.ts
new file mode 100644
index 00000000..a9548bd0
--- /dev/null
+++ b/frontend/src/app/chat/model/chat.ts
@@ -0,0 +1,12 @@
+import { Message } from './message';
+
+export interface Chat {
+  id?: string;
+  uid?: string;
+  createdAt: number;
+  count: number;
+  messages: Message[];
+  participants: string[];
+  ownerId: string;
+  typing: string[];
+}
diff --git a/frontend/src/app/chat/model/message.ts b/frontend/src/app/chat/model/message.ts
new file mode 100644
index 00000000..377b8fcc
--- /dev/null
+++ b/frontend/src/app/chat/model/message.ts
@@ -0,0 +1,13 @@
+import { User } from './user';
+
+export interface Attachment {
+  name: string;
+}
+
+export interface Message {
+  content: string;
+  uid: string;
+  createdAt: number;
+  user: User;
+  attachments: Attachment[];
+}
diff --git a/frontend/src/app/chat/model/user.ts b/frontend/src/app/chat/model/user.ts
new file mode 100644
index 00000000..9f42b7e5
--- /dev/null
+++ b/frontend/src/app/chat/model/user.ts
@@ -0,0 +1,6 @@
+export interface User {
+  uid: string;
+  email: string;
+  displayName: string;
+  photoUrl: string;
+}
diff --git a/frontend/src/app/chat/services/api/api-chat.service.spec.ts b/frontend/src/app/chat/services/api/api-chat.service.spec.ts
new file mode 100644
index 00000000..ea14a857
--- /dev/null
+++ b/frontend/src/app/chat/services/api/api-chat.service.spec.ts
@@ -0,0 +1,12 @@
+import { TestBed } from '@angular/core/testing';
+
+import { ApiChatService } from './api-chat.service';
+
+describe('ApiChatService', () => {
+  beforeEach(() => TestBed.configureTestingModule({}));
+
+  it('should be created', () => {
+    const service: ApiChatService = TestBed.get(ApiChatService);
+    expect(service).toBeTruthy();
+  });
+});
diff --git a/frontend/src/app/chat/services/api/api-chat.service.ts b/frontend/src/app/chat/services/api/api-chat.service.ts
new file mode 100644
index 00000000..3167a4d7
--- /dev/null
+++ b/frontend/src/app/chat/services/api/api-chat.service.ts
@@ -0,0 +1,40 @@
+import { Injectable } from '@angular/core';
+import { ChatBaseService } from '../chat-base.service';
+import { Message } from '../../model/message';
+import { Chat } from '../../model/chat';
+import { Observable } from 'rxjs';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class ApiChatService extends ChatBaseService {
+  constructor() {
+    super();
+  }
+
+  create(): Promise<boolean> {
+    return undefined;
+  }
+
+  deleteIsTyping(chatId: string): Promise<void> {
+    return undefined;
+  }
+
+  deleteMessage(chat: Chat, msg: Message): Promise<void> {
+    return undefined;
+  }
+
+  getHistory(chatId: string): Observable<any> {
+    return undefined;
+  }
+
+  sendIsTyping(chatId: string): Promise<void> {
+    return undefined;
+  }
+
+  sendMessage(chatId: string, content: string): Promise<void> {
+    return undefined;
+  }
+
+  buildChat(source: Observable<any>) {}
+}
diff --git a/frontend/src/app/chat/services/chat-base.service.ts b/frontend/src/app/chat/services/chat-base.service.ts
new file mode 100644
index 00000000..9158cf02
--- /dev/null
+++ b/frontend/src/app/chat/services/chat-base.service.ts
@@ -0,0 +1,27 @@
+import { Message } from '../model/message';
+import { Chat } from '../model/chat';
+import { Observable } from 'rxjs';
+import { ServicesConfig } from './services-config';
+import { Injectable, Optional } from '@angular/core';
+
+export abstract class ChatBaseService {
+  constructor(@Optional() config?: ServicesConfig) {
+    if (config) {
+      console.log('Config:', config);
+    }
+  }
+
+  abstract getHistory(chatId: string): Observable<any>;
+
+  // abstract create(): Promise<boolean>;
+  //
+  // abstract sendMessage(chatId: string, content: string): Promise<void>;
+  //
+  // abstract deleteMessage(chat: Chat, msg: Message): Promise<void>;
+  //
+  // abstract sendIsTyping(chatId: string): Promise<void>;
+  //
+  // abstract deleteIsTyping(chatId: string): Promise<void>;
+  //
+  // abstract buildChat(source: Observable<any>) ;
+}
diff --git a/frontend/src/app/chat/services/firebase/firebase-chat.service.ts b/frontend/src/app/chat/services/firebase/firebase-chat.service.ts
new file mode 100644
index 00000000..a9262933
--- /dev/null
+++ b/frontend/src/app/chat/services/firebase/firebase-chat.service.ts
@@ -0,0 +1,166 @@
+import { Injectable, Optional } from '@angular/core';
+import { Router } from '@angular/router';
+import { map, tap, switchMap, flatMap } from 'rxjs/operators';
+import { Observable, combineLatest, of, merge } from 'rxjs';
+import { catchError } from 'rxjs/operators';
+import { User } from '../../model/user';
+import { ChatBaseService } from '../chat-base.service';
+import { Message } from '../../model/message';
+import { Chat } from '../../model/chat';
+import { ServicesConfig } from '../services-config';
+import * as moment from 'moment';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class FirebaseChatService extends ChatBaseService {
+  userDictionary = {};
+
+  constructor(
+    // private auth: FirebaseAuthService,
+    private router: Router,
+    @Optional() config?: ServicesConfig
+  ) {
+    super(config);
+  }
+
+  getHistory(chatId: string): Observable<any> {
+    return new Observable<any>();
+  }
+
+  getParticipatingChats() {
+    // return this.auth.user$.pipe(
+    //   switchMap(user => {
+    //     const participatingChats = this.afs
+    //       .collection('chats', (ref: any) =>
+    //         ref.where('participants', 'array-contains', user.uid)
+    //       )
+    //       .snapshotChanges();
+    //     return participatingChats.pipe(
+    //       map((actions: any) => {
+    //         return actions.map((a: any) => {
+    //           const chatData: any = a.payload.doc.data();
+    //           const id = a.payload.doc.id;
+    //           return { id, ...chatData };
+    //         });
+    //       })
+    //     );
+    //   })
+    // );
+  }
+
+  async create(): Promise<boolean> {
+    // Fetch user and wait for result
+    // const { uid } = await this.auth.getUser();
+    const uid = 'uid';
+
+    // Init new chat data
+    const data: Chat = {
+      id: '12354', // TODO generate guid
+      createdAt: Date.now(),
+      count: 0,
+      messages: [],
+      participants: [uid],
+      ownerId: uid,
+      typing: [],
+    };
+
+    // Add new chat data to firestore and wait for result
+    // TODO save chat
+
+    // Route to new chat in chat component
+    return this.router.navigate(['chats', data.id]);
+  }
+
+  async sendIsTyping(chatId: string): Promise<void> {
+    // const { uid } = await this.auth.getUser();
+    const uid = 'uid';
+
+    // if (uid) {
+    //   const ref = this.afs.collection('chats').doc(chatId);
+    //   return ref.update({
+    //     typing: firebase.firestore.FieldValue.arrayUnion(uid)
+    //   });
+    // }
+  }
+
+  async deleteIsTyping(chatId: string): Promise<void> {
+    // const { uid } = await this.auth.getUser();
+    //
+    // if (uid) {
+    //   const ref = this.afs.collection('chats').doc(chatId);
+    //   return ref.update({
+    //     typing: firebase.firestore.FieldValue.arrayRemove(uid)
+    //   });
+    // }
+  }
+
+  async sendMessage(chatId: string, content: string): Promise<void> {
+    // const { uid } = await this.auth.getUser();
+    //
+    // const data = {
+    //   uid,
+    //   content,
+    //   createdAt: firebase.firestore.Timestamp.now()
+    // };
+    //
+    // if (uid) {
+    //   const ref = this.afs.collection('chats').doc(chatId);
+    //   return ref.update({
+    //     messages: firebase.firestore.FieldValue.arrayUnion(data)
+    //   });
+    // }
+  }
+  //
+  async deleteMessage(chat: Chat, msg: Message) {
+    // const { uid } = await this.auth.getUser();
+    //
+    // const ref = this.afs.collection('chats').doc(chat.id);
+    // if (chat.uid === uid || msg.uid === uid) {
+    //   delete msg.user;
+    //   return ref.update({
+    //     messages: firebase.firestore.FieldValue.arrayRemove(msg)
+    //   });
+    // }
+  }
+  //
+  // buildChat(chat$: Observable<any>): Observable<any> {
+  //   let chat: any;
+  //
+  //   return chat$.pipe(
+  //     switchMap(c => {
+  //       chat = c;
+  //       // Get all users in the chat -> find user data since only uid is known
+  //       const uids = Array.from(
+  //         new Set(c.messages.map((message: any) => message.uid))
+  //       );
+  //       const users = this.fetchUsers(uids);
+  //       return users.length ? combineLatest(users) : of([]);
+  //     }),
+  //     map(users => {
+  //       this.buildUserDictionary(users);
+  //       // Augment message data with newly fetched user data
+  //       chat.messages = chat.messages.map((message: any) => {
+  //         return {
+  //           ...message,
+  //           createdAt: moment(message.createdAt.toDate()),
+  //           user: this.userDictionary[message.uid]
+  //         };
+  //       });
+  //       return chat;
+  //     })
+  //   );
+  // }
+  //
+  // private buildUserDictionary(users: unknown[]) {
+  //   users.forEach(user => (this.userDictionary[(user as User).uid] = user));
+  // }
+  //
+  // private fetchUsers(uids: unknown[]): Observable<any>[] {
+  //   return uids.map(uid => this.afs.doc(`users/${uid}`).valueChanges());
+  // }
+  //
+  // getUserById(typerId) {
+  //   return this.userDictionary[typerId];
+  // }
+}
diff --git a/frontend/src/app/chat/services/services-config.ts b/frontend/src/app/chat/services/services-config.ts
new file mode 100644
index 00000000..f8278087
--- /dev/null
+++ b/frontend/src/app/chat/services/services-config.ts
@@ -0,0 +1,12 @@
+export class ServicesConfig {
+  firebase:
+    | {
+        chat: string;
+      }
+    | undefined;
+  apiEndpoints:
+    | {
+        history: string;
+      }
+    | undefined;
+}
diff --git a/frontend/src/app/chat/services/services.module.ts b/frontend/src/app/chat/services/services.module.ts
new file mode 100644
index 00000000..2ca4af19
--- /dev/null
+++ b/frontend/src/app/chat/services/services.module.ts
@@ -0,0 +1,27 @@
+import { ModuleWithProviders, NgModule, Optional, SkipSelf } from '@angular/core';
+import { CommonModule } from '@angular/common';
+import { ChatBaseService } from './chat-base.service';
+import { ServicesConfig } from './services-config';
+
+/**
+ * Help: https://angular.io/guide/singleton-services
+ */
+
+@NgModule({
+  declarations: [],
+  imports: [CommonModule],
+})
+export class ServicesModule {
+  constructor(@Optional() @SkipSelf() parentModule?: ServicesModule) {
+    if (parentModule) {
+      throw new Error('GreetingModule is already loaded. Import it in the AppModule only');
+    }
+  }
+
+  static forRoot(config: ServicesConfig): ModuleWithProviders {
+    return {
+      ngModule: ServicesModule,
+      providers: [{ provide: ServicesConfig, useValue: config }],
+    };
+  }
+}
diff --git a/src/agent/agentStateService/agentStateService.int.ts b/src/agent/agentStateService/agentStateService.int.ts
index 28aa364f..22ccb7be 100644
--- a/src/agent/agentStateService/agentStateService.int.ts
+++ b/src/agent/agentStateService/agentStateService.int.ts
@@ -2,7 +2,7 @@ import fs from 'fs';
 import { expect } from 'chai';
 import { AgentContext } from '#agent/agentContextTypes';
 import { AgentStateService } from '#agent/agentStateService/agentStateService';
-import { FirestoreAgentStateService } from '#agent/agentStateService/firestoreAgentStateService';
+import { FirestoreAgentStateService } from '#modules/firestore/firestoreAgentStateService';
 
 describe('AgentStateService Integration Tests', () => {
 	let service: AgentStateService;
diff --git a/src/app.ts b/src/app.ts
index c00d9af9..b383efe2 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -1,17 +1,17 @@
 import { AgentStateService } from '#agent/agentStateService/agentStateService';
 import { FileAgentStateService } from '#agent/agentStateService/fileAgentStateService';
-import { FirestoreAgentStateService } from '#agent/agentStateService/firestoreAgentStateService';
 import { InMemoryAgentStateService } from '#agent/agentStateService/inMemoryAgentStateService';
 import { RouteDefinition } from '#fastify/fastifyApp';
-import { FirestoreLlmCallService } from '#llm/llmCallService/firestoreLlmCallService';
 import { InMemoryLlmCallService } from '#llm/llmCallService/inMemoryLlmCallService';
 import { LlmCallService } from '#llm/llmCallService/llmCallService';
+import { FirestoreAgentStateService } from '#modules/firestore/firestoreAgentStateService';
+import { FirestoreCodeReviewService } from '#modules/firestore/firestoreCodeReviewService';
+import { FirestoreLlmCallService } from '#modules/firestore/firestoreLlmCallService';
+import { FirestoreUserService } from '#modules/firestore/firestoreUserService';
 import { logger } from '#o11y/logger';
 import { CodeReviewService } from '#swe/codeReview/codeReviewService';
-import { FirestoreCodeReviewService } from '#swe/codeReview/firestoreCodeReviewService';
 import { InMemoryCodeReviewService } from '#swe/codeReview/memoryCodeReviewService';
 import { FileUserService } from '#user/userService/fileUserService';
-import { FirestoreUserService } from '#user/userService/firestoreUserService';
 import { InMemoryUserService } from '#user/userService/inMemoryUserService';
 import { UserService } from '#user/userService/userService';
 import { FileFunctionCacheService } from './cache/fileFunctionCacheService';
diff --git a/src/chat/chatTypes.ts b/src/chat/chatTypes.ts
new file mode 100644
index 00000000..d6c8ac28
--- /dev/null
+++ b/src/chat/chatTypes.ts
@@ -0,0 +1,13 @@
+import { LlmMessage } from '#llm/llm';
+
+export interface Chat {
+	id: string;
+	/** When a chat is branched from the original thread by deleting/updating messages etc */
+	parentId?: string;
+	messages: LlmMessage[];
+}
+
+export interface ChatService {
+	loadChat(chatId: string): Promise<Chat>;
+	saveChat(chatId: string, messages: LlmMessage[]): Promise<Chat>;
+}
diff --git a/src/fastify/hooks.ts b/src/fastify/hooks.ts
index 93830fd0..48f9a175 100644
--- a/src/fastify/hooks.ts
+++ b/src/fastify/hooks.ts
@@ -1,6 +1,6 @@
 import { FastifyInstance } from 'fastify';
+import { DEFAULT_HEALTHCHECK } from '#fastify/fastifyApp';
 import { sendBadRequest } from './responses';
-import {DEFAULT_HEALTHCHECK} from "#fastify/fastifyApp";
 
 export interface RouteInterface {
 	method: string | string[];
diff --git a/src/agent/agentStateService/firestoreAgentStateService.ts b/src/modules/firestore/firestoreAgentStateService.ts
similarity index 97%
rename from src/agent/agentStateService/firestoreAgentStateService.ts
rename to src/modules/firestore/firestoreAgentStateService.ts
index 0bd7fdbf..d95e9a44 100644
--- a/src/agent/agentStateService/firestoreAgentStateService.ts
+++ b/src/modules/firestore/firestoreAgentStateService.ts
@@ -2,11 +2,11 @@ import { DocumentSnapshot, Firestore } from '@google-cloud/firestore';
 import { LlmFunctions } from '#agent/LlmFunctions';
 import { deserializeAgentContext, serializeContext } from '#agent/agentContextLocalStorage';
 import { AgentContext, AgentRunningState } from '#agent/agentContextTypes';
+import { AgentStateService } from '#agent/agentStateService/agentStateService';
 import { functionFactory } from '#functionSchema/functionDecorators';
 import { logger } from '#o11y/logger';
 import { span } from '#o11y/trace';
 import { firestoreDb } from '../../firestore';
-import { AgentStateService } from './agentStateService';
 
 /**
  * Google Firestore implementation of AgentStateService
diff --git a/src/modules/firestore/firestoreChatService.ts b/src/modules/firestore/firestoreChatService.ts
new file mode 100644
index 00000000..638c47c6
--- /dev/null
+++ b/src/modules/firestore/firestoreChatService.ts
@@ -0,0 +1,57 @@
+import { Firestore } from '@google-cloud/firestore';
+import { Chat, ChatService } from '#chat/chatTypes';
+import { LlmMessage } from '#llm/llm';
+import { logger } from '#o11y/logger';
+import { span } from '#o11y/trace';
+import { firestoreDb } from '../../firestore';
+
+/**
+ * Google Firestore implementation of ChatService
+ */
+export class FirestoreChatService implements ChatService {
+	private db: Firestore;
+
+	constructor() {
+		this.db = firestoreDb();
+	}
+
+	@span()
+	async loadChat(chatId: string): Promise<Chat> {
+		try {
+			const docRef = this.db.doc(`Chats/${chatId}`);
+			const docSnap = await docRef.get();
+
+			if (!docSnap.exists) {
+				logger.warn(`Chat with id ${chatId} not found`);
+				throw new Error(`Chat with id ${chatId} not found`);
+			}
+
+			const data = docSnap.data();
+			return {
+				id: chatId,
+				parentId: data.parentId,
+				messages: data.messages,
+			};
+		} catch (error) {
+			logger.error(error, `Error loading chat ${chatId}`);
+			throw error;
+		}
+	}
+
+	@span()
+	async saveChat(chatId: string, messages: LlmMessage[]): Promise<Chat> {
+		try {
+			const docRef = this.db.doc(`Chats/${chatId}`);
+			const chat: Chat = {
+				id: chatId,
+				messages,
+			};
+
+			await docRef.set(chat, { merge: true });
+			return chat;
+		} catch (error) {
+			logger.error(error, `Error saving chat ${chatId}`);
+			throw error;
+		}
+	}
+}
diff --git a/src/swe/codeReview/firestoreCodeReviewService.test.ts b/src/modules/firestore/firestoreCodeReviewService.test.ts
similarity index 100%
rename from src/swe/codeReview/firestoreCodeReviewService.test.ts
rename to src/modules/firestore/firestoreCodeReviewService.test.ts
diff --git a/src/swe/codeReview/firestoreCodeReviewService.ts b/src/modules/firestore/firestoreCodeReviewService.ts
similarity index 98%
rename from src/swe/codeReview/firestoreCodeReviewService.ts
rename to src/modules/firestore/firestoreCodeReviewService.ts
index 19bf8bcd..bb3bb080 100644
--- a/src/swe/codeReview/firestoreCodeReviewService.ts
+++ b/src/modules/firestore/firestoreCodeReviewService.ts
@@ -2,7 +2,6 @@ import { DocumentSnapshot, Firestore } from '@google-cloud/firestore';
 import { logger } from '#o11y/logger';
 import { CodeReviewConfig } from '#swe/codeReview/codeReviewModel';
 import { CodeReviewService } from '#swe/codeReview/codeReviewService';
-import { envVar } from '#utils/env-var';
 import { firestoreDb } from '../../firestore';
 
 export class FirestoreCodeReviewService implements CodeReviewService {
diff --git a/src/llm/llmCallService/firestoreLlmCallService.test.ts b/src/modules/firestore/firestoreLlmCallService.test.ts
similarity index 98%
rename from src/llm/llmCallService/firestoreLlmCallService.test.ts
rename to src/modules/firestore/firestoreLlmCallService.test.ts
index 84e5d120..a550dce5 100644
--- a/src/llm/llmCallService/firestoreLlmCallService.test.ts
+++ b/src/modules/firestore/firestoreLlmCallService.test.ts
@@ -3,9 +3,9 @@ import { expect } from 'chai';
 import sinon from 'sinon';
 import { logger } from '#o11y/logger';
 
-import { FirestoreLlmCallService } from '#llm/llmCallService/firestoreLlmCallService';
 import { CreateLlmRequest, LlmCall } from '#llm/llmCallService/llmCall';
 import { LlmCallService } from '#llm/llmCallService/llmCallService';
+import { FirestoreLlmCallService } from '#modules/firestore/firestoreLlmCallService';
 
 const emulatorHost = process.env.FIRESTORE_EMULATOR_HOST;
 
diff --git a/src/llm/llmCallService/firestoreLlmCallService.ts b/src/modules/firestore/firestoreLlmCallService.ts
similarity index 100%
rename from src/llm/llmCallService/firestoreLlmCallService.ts
rename to src/modules/firestore/firestoreLlmCallService.ts
diff --git a/src/user/userService/firestoreUserService.test.ts b/src/modules/firestore/firestoreUserService.test.ts
similarity index 95%
rename from src/user/userService/firestoreUserService.test.ts
rename to src/modules/firestore/firestoreUserService.test.ts
index 4effd16e..cc822ed3 100644
--- a/src/user/userService/firestoreUserService.test.ts
+++ b/src/modules/firestore/firestoreUserService.test.ts
@@ -1,11 +1,11 @@
 import { fail } from 'node:assert';
 import axios from 'axios';
 import { assert, expect } from 'chai';
-import { FirestoreLlmCallService } from '#llm/llmCallService/firestoreLlmCallService';
+import { FirestoreLlmCallService } from '#modules/firestore/firestoreLlmCallService';
 import { logger } from '#o11y/logger';
-import { User } from '../user';
+import { User } from '#user/user';
+import { InMemoryUserService } from '#user/userService/inMemoryUserService';
 import { FirestoreUserService } from './firestoreUserService';
-import { InMemoryUserService } from './inMemoryUserService';
 
 const emulatorHost = process.env.FIRESTORE_EMULATOR_HOST;
 
diff --git a/src/user/userService/firestoreUserService.ts b/src/modules/firestore/firestoreUserService.ts
similarity index 97%
rename from src/user/userService/firestoreUserService.ts
rename to src/modules/firestore/firestoreUserService.ts
index ce75339f..081d2fac 100644
--- a/src/user/userService/firestoreUserService.ts
+++ b/src/modules/firestore/firestoreUserService.ts
@@ -2,10 +2,10 @@ import { DocumentSnapshot, Firestore } from '@google-cloud/firestore';
 import { LlmCall } from '#llm/llmCallService/llmCall';
 import { logger } from '#o11y/logger';
 import { span } from '#o11y/trace';
+import { User } from '#user/user';
 import { isSingleUser } from '#user/userService/userContext';
+import { UserService } from '#user/userService/userService';
 import { envVar } from '#utils/env-var';
-import { User } from '../user';
-import { UserService } from './userService';
 
 /*** Google Firestore implementation of UserService*/
 export class FirestoreUserService implements UserService {
diff --git a/tsconfig.json b/tsconfig.json
index 7425d321..86e3effc 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -21,7 +21,9 @@
     "baseUrl": "./",
     "paths": {
       "#agent/*": ["./src/agent/*"],
+      "#chat/*": ["./src/chat/*"],
       "#fastify/*": ["./src/fastify/*"],
+      "#firestore*": ["./src/modules/firestore*"],
       "#functionSchema/*": ["./src/functionSchema/*"],
       "#functions/*": ["./src/functions/*"],
       "#llm/*": ["./src/llm/*"],
@@ -29,6 +31,7 @@
       "#o11y/*": ["./src/o11y/*"],
       "#services/*": ["./src/services/*"],
       "#modules/*": ["./src/modules/*"],
+      "#slack/*": ["./src/modules/slack/*"],
       "#swe/*": ["./src/swe/*"],
       "#user/*": ["./src/user/*"],
       "#utils/*": ["./src/utils/*"]