diff --git a/backend/main.py b/backend/main.py
new file mode 100644
index 0000000..e6187ed
--- /dev/null
+++ b/backend/main.py
@@ -0,0 +1,205 @@
+from datetime import datetime, timedelta
+from typing import List
+from uuid import uuid4
+
+from fastapi import Depends, FastAPI, HTTPException, status
+from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
+from jose import JWTError, jwt
+
+import backend.document_store as document_store
+from database.database import Database
+from backend.document_store import StorageBackend
+from backend.model import Doc, Message
+from backend.user_management import (
+    ALGORITHM,
+    SECRET_KEY,
+    User,
+    authenticate_user,
+    create_access_token,
+    create_user,
+    get_user,
+    user_exists,
+)
+
+app = FastAPI()
+
+
+############################################
+###           Authentication             ###
+############################################
+
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="login")
+
+
+async def get_current_user(token: str = Depends(oauth2_scheme)) -> User:
+    """Get the current user by decoding the JWT token."""
+    credentials_exception = HTTPException(
+        status_code=status.HTTP_401_UNAUTHORIZED,
+        detail="Could not validate credentials",
+        headers={"WWW-Authenticate": "Bearer"},
+    )
+    try:
+        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
+        email: str = payload.get("email")  # 'sub' is commonly used to store user identity
+        if email is None:
+            raise credentials_exception
+        # Here you should fetch the user from the database by user_id
+        user = get_user(email)
+        if user is None:
+            raise credentials_exception
+        return user
+    except JWTError:
+        raise credentials_exception
+
+
+@app.post("/user/signup")
+async def signup(user: User) -> dict:
+    """Sign up a new user."""
+    if user_exists(user.email):
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST, detail=f"User {user.email} already registered"
+        )
+
+    create_user(user)
+    return {"email": user.email}
+
+
+@app.delete("/user/")
+async def delete_user(current_user: User = Depends(get_current_user)) -> dict:
+    """Delete an existing user."""
+    email = current_user.email
+    try:
+        user = get_user(email)
+        if user is None:
+            raise HTTPException(
+                status_code=status.HTTP_404_NOT_FOUND, detail=f"User {email} not found"
+            )
+        delete_user(email)
+        return {"detail": f"User {email} deleted"}
+    except Exception:
+        raise HTTPException(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="Internal Server Error"
+        )
+
+
+@app.post("/user/login")
+async def login(form_data: OAuth2PasswordRequestForm = Depends()) -> dict:
+    """Log in a user and return an access token."""
+    user = authenticate_user(form_data.username, form_data.password)
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect username or password",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    access_token_expires = timedelta(minutes=60)
+    access_token = create_access_token(data=user.model_dump(), expires_delta=access_token_expires)
+    return {"access_token": access_token, "token_type": "bearer"}
+
+
+@app.get("/user/me")
+async def user_me(current_user: User = Depends(get_current_user)) -> User:
+    """Get the current user's profile."""
+    return current_user
+
+
+############################################
+###               Chat                   ###
+############################################
+
+@app.post("/chat/new")
+async def chat_new(current_user: User = Depends(get_current_user)) -> dict:
+    chat_id = str(uuid4())
+    timestamp = datetime.now().isoformat()
+    user_id = current_user.email
+    with Database() as connection:
+        connection.query(
+            "INSERT INTO chat (id, timestamp, user_id) VALUES (?, ?, ?)",
+            (chat_id, timestamp, user_id),
+        )
+    return {"chat_id": chat_id}
+
+@app.post("/chat/{chat_id}/user_message")
+async def chat_prompt(message: Message, current_user: User = Depends(get_current_user)) -> dict:
+    with Database() as connection:
+        connection.query(
+            "INSERT INTO message (id, timestamp, chat_id, sender, content) VALUES (?, ?, ?, ?, ?)",
+            (message.id, message.timestamp, message.chat_id, message.sender, message.content),
+        )
+    
+    model_response = Message(
+        id=str(uuid4()),
+        timestamp=datetime.now().isoformat(),
+        chat_id=message.chat_id,
+        sender="assistant",
+        content=f"Unique response: {uuid4()}",
+    )
+
+    with Database() as connection:
+        connection.query(
+            "INSERT INTO message (id, timestamp, chat_id, sender, content) VALUES (?, ?, ?, ?, ?)",
+            (model_response.id, model_response.timestamp, model_response.chat_id, model_response.sender, model_response.content),
+        )
+    return {"message": model_response}
+
+
+@app.post("/chat/regenerate")
+async def chat_regenerate(current_user: User = Depends(get_current_user)) -> dict:
+    """Regenerate a chat session for the current user."""
+    pass
+
+
+@app.get("/chat/list")
+async def chat_list(current_user: User = Depends(get_current_user)) -> List[dict]:
+    """Get a list of chat sessions for the current user."""
+    pass
+
+
+@app.get("/chat/{chat_id}")
+async def chat(chat_id: str, current_user: User = Depends(get_current_user)) -> dict:
+    """Get details of a specific chat session."""
+    pass
+
+
+############################################
+###               Feedback               ###
+############################################
+
+
+@app.post("/feedback/{message_id}/thumbs_up")
+async def feedback_thumbs_up(
+    message_id: str, current_user: User = Depends(get_current_user)
+) -> None:
+    with Database() as connection:
+        connection.query(
+            "INSERT INTO feedback (id, message_id, feedback) VALUES (?, ?, ?)",
+            (str(uuid4()), message_id, "thumbs_up"),
+        )
+
+
+@app.post("/feedback/{message_id}/thumbs_down")
+async def feedback_thumbs_down(
+    message_id: str, current_user: User = Depends(get_current_user)
+) -> None:
+    with Database() as connection:
+        connection.query(
+            "INSERT INTO feedback (id, message_id, feedback) VALUES (?, ?, ?)",
+            (str(uuid4()), message_id, "thumbs_down"),
+        )
+
+
+############################################
+###                Other                 ###
+############################################
+
+
+@app.post("/index/documents")
+async def index_documents(chunks: List[Doc], bucket: str, storage_backend: StorageBackend) -> None:
+    """Index documents in a specified storage backend."""
+    document_store.store_documents(chunks, bucket, storage_backend)
+
+
+if __name__ == "__main__":
+    import uvicorn
+
+    uvicorn.run(app, host="0.0.0.0", port=8000)
diff --git a/backend/model.py b/backend/model.py
new file mode 100644
index 0000000..6c49ec1
--- /dev/null
+++ b/backend/model.py
@@ -0,0 +1,21 @@
+from datetime import datetime
+from uuid import uuid4
+from langchain.docstore.document import Document
+from pydantic import BaseModel
+
+class Message(BaseModel):
+    id: str
+    timestamp: str
+    chat_id: str
+    sender: str
+    content: str
+
+class Doc(BaseModel):
+    """Represents a document with content and associated metadata."""
+
+    content: str
+    metadata: dict
+
+    def to_langchain_document(self) -> Document:
+        """Converts the current Doc instance into a langchain Document."""
+        return Document(page_content=self.content, metadata=self.metadata)
diff --git a/database/database.sqlite b/database/database.sqlite
new file mode 100644
index 0000000..7c5a9c5
Binary files /dev/null and b/database/database.sqlite differ
diff --git a/database/database_init.sql b/database/database_init.sql
new file mode 100644
index 0000000..d3f17c9
--- /dev/null
+++ b/database/database_init.sql
@@ -0,0 +1,34 @@
+-- Go to https://dbdiagram.io/d/RAGAAS-63dbdcc6296d97641d7e07c8
+-- Make your changes
+-- Export > Export to PostgresSQL (or other)
+-- Translate to SQLite (works with a cmd+k in Cursor, or https://www.rebasedata.com/convert-postgresql-to-sqlite-online)
+-- Paste here
+-- Replace "CREATE TABLE" with "CREATE TABLE IF NOT EXISTS"
+
+CREATE TABLE IF NOT EXISTS "user" (
+    "email" TEXT PRIMARY KEY,
+    "password" TEXT
+);
+
+CREATE TABLE IF NOT EXISTS "chat" (
+    "id" TEXT PRIMARY KEY,
+    "timestamp" TEXT,
+    "user_id" TEXT,
+    FOREIGN KEY ("user_id") REFERENCES "user" ("email")
+);
+
+CREATE TABLE IF NOT EXISTS "message" (
+    "id" TEXT PRIMARY KEY,
+    "timestamp" TEXT,
+    "chat_id" TEXT,
+    "sender" TEXT,
+    "content" TEXT,
+    FOREIGN KEY ("chat_id") REFERENCES "chat" ("id")
+);
+
+CREATE TABLE IF NOT EXISTS "feedback" (
+    "id" TEXT PRIMARY KEY,
+    "message_id" TEXT,
+    "feedback" TEXT,
+    FOREIGN KEY ("message_id") REFERENCES "message" ("id")
+);
diff --git a/frontend/lib/chat.py b/frontend/lib/chat.py
new file mode 100644
index 0000000..47d1c73
--- /dev/null
+++ b/frontend/lib/chat.py
@@ -0,0 +1,60 @@
+from uuid import uuid4
+from datetime import datetime
+
+import streamlit as st
+
+from dataclasses import dataclass, asdict
+from streamlit_feedback import streamlit_feedback
+
+@dataclass
+class Message:
+    sender: str
+    content: str
+    chat_id: str
+    id: str = None
+    timestamp: str = None
+
+    def __post_init__(self):
+        self.id = str(uuid4()) if self.id is None else self.id
+        self.timestamp = datetime.now().isoformat() if self.timestamp is None else self.timestamp
+
+def chat():
+    prompt = st.chat_input("Say something")
+
+    if prompt:
+        if len(st.session_state.get("messages", [])) == 0:
+            chat_id = new_chat()
+        else:
+            chat_id = st.session_state.get("chat_id")
+
+        st.session_state.get("messages").append(Message("user", prompt, chat_id))
+        response = send_prompt(st.session_state.get("messages")[-1])
+        st.session_state.get("messages").append(Message(**response))
+
+    with st.container(border=True):
+        for message in st.session_state.get("messages", []):
+            with st.chat_message(message.sender):
+                st.write(message.content)
+        if len(st.session_state.get("messages", [])) > 0 and len(st.session_state.get("messages")) % 2 == 0:
+            streamlit_feedback(key=str(len(st.session_state.get("messages"))), feedback_type="thumbs", on_submit=lambda feedback: send_feedback(st.session_state.get("messages")[-1].id, feedback))
+
+
+def new_chat():
+    session = st.session_state.get("session")
+    response = session.post("/chat/new")
+    st.session_state["chat_id"] = response.json()["chat_id"]
+    st.session_state["messages"] = []
+    return response.json()["chat_id"]
+
+def send_prompt(message: Message):
+    session = st.session_state.get("session")
+    response = session.post(f"/chat/{message.chat_id}/user_message", json=asdict(message))
+    print(response.headers)
+    print(response.text)
+    return response.json()["message"]
+
+def send_feedback(message_id: str, feedback: str):
+    feedback = "thumbs_up" if feedback["score"] == "👍" else "thumbs_down"
+    session = st.session_state.get("session")
+    response = session.post(f"/feedback/{message_id}/{feedback}")
+    return response.text
\ No newline at end of file