diff --git a/app/app.py b/app/app.py
index 089c2fc..3c820a7 100644
--- a/app/app.py
+++ b/app/app.py
@@ -1,3 +1,140 @@
+import os, json, uuid
+import requests
+from flask import Flask, Response, request, jsonify, session, redirect, url_for
+from authlib.integrations.flask_client import OAuth
+from functools import wraps
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+from markdown import markdown
+
+from config import Config
+from models import Base, Conversation, Message, Attachment
+
+app = Flask(__name__)
+app.config.from_object(Config)
+app.secret_key = app.config["SECRET_KEY"]
+
+engine = create_engine(os.getenv("DATABASE_URL"))
+SessionLocal = sessionmaker(bind=engine)
+Base.metadata.create_all(engine)
+
+oauth = OAuth(app)
+google = oauth.register(
+    name="google",
+    client_id=app.config["GOOGLE_CLIENT_ID"],
+    client_secret=app.config["GOOGLE_CLIENT_SECRET"],
+    access_token_url="https://oauth2.googleapis.com/token",
+    authorize_url="https://accounts.google.com/o/oauth2/v2/auth",
+    api_base_url="https://www.googleapis.com/oauth2/v2/",
+    client_kwargs={"scope": "openid email profile"},
+)
+
+def login_required(f):
+    @wraps(f)
+    def wrapper(*args, **kwargs):
+        if "user" not in session:
+            return redirect(url_for("login"))
+        return f(*args, **kwargs)
+    return wrapper
+
+@app.route("/login")
+def login():
+    return google.authorize_redirect(app.config["GOOGLE_REDIRECT_URI"])
+
+@app.route("/oauth/callback")
+def oauth_callback():
+    token = google.authorize_access_token()
+    user_info = google.get("userinfo").json()
+    session["user"] = user_info
+    return redirect("/")
+
+@app.route("/api/new_conversation", methods=["POST"])
+@login_required
+def new_conversation():
+    db = SessionLocal()
+    cid = str(uuid.uuid4())
+    title = request.json.get("title", "New conversation")
+    conv = Conversation(id=cid, title=title)
+    db.add(conv)
+    db.commit()
+    db.close()
+    return jsonify({"conversation_id": cid, "title": title})
+
+@app.route("/api/conversations")
+@login_required
+def list_conversations():
+    db = SessionLocal()
+    convs = db.query(Conversation).all()
+    data = [{"id": c.id, "title": c.title} for c in convs]
+    db.close()
+    return jsonify(data)
+
+@app.route("/api/history/<cid>")
+@login_required
+def history(cid):
+    db = SessionLocal()
+    msgs = db.query(Message).filter_by(conversation_id=cid).order_by(Message.created_at).all()
+    data = [{"role": m.role, "content": markdown(m.content)} for m in msgs]
+    db.close()
+    return jsonify(data)
+
+@app.route("/api/attachment/<cid>", methods=["POST"])
+@login_required
+def upload_attachment(cid):
+    db = SessionLocal()
+    file = request.files.get("file")
+    if not file:
+        return jsonify({"error": "No file"}), 400
+    content = file.read().decode("latin1")
+    att = Attachment(
+        id=str(uuid.uuid4()),
+        conversation_id=cid,
+        filename=file.filename,
+        mime_type=file.mimetype,
+        data=content,
+    )
+    db.add(att)
+    db.commit()
+    db.close()
+    return jsonify({"status": "ok"})
+
+@app.route("/api/stream")
+@login_required
+def stream():
+    cid = request.args.get("conversation_id")
+    model = request.args.get("model", "llama3.2")
+    prompt = request.args.get("prompt")
+
+    db = SessionLocal()
+    db.add(Message(id=str(uuid.uuid4()), conversation_id=cid, role="user", content=prompt))
+    db.commit()
+
+    def generate():
+        url = f"{app.config['OLLAMA_BASE_URL']}/api/generate"
+        payload = {"model": model, "prompt": prompt, "stream": True}
+
+        with requests.post(url, json=payload, stream=True) as r:
+            buffer = ""
+            for line in r.iter_lines():
+                if not line:
+                    continue
+                try:
+                    data = json.loads(line.decode())
+                    token = data.get("response", "")
+                    buffer += token
+                    # streaming animation: send partial buffer
+                    yield f"data: {json.dumps({'token': token})}\n\n"
+                except:
+                    continue
+            db.add(Message(id=str(uuid.uuid4()), conversation_id=cid, role="assistant", content=buffer))
+            db.commit()
+            db.close()
+
+    return Response(generate(), mimetype="text/event-stream")
+
+
+# ***
+
 import json
 import requests
 from flask import Flask, Response, request, jsonify, session, redirect, url_for