diff --git a/backend/Dockerfile b/backend/Dockerfile
index b862b2b..3639ea9 100644
--- a/backend/Dockerfile
+++ b/backend/Dockerfile
@@ -2,6 +2,10 @@ FROM python:3.10-slim
 
 WORKDIR /app
 
-RUN pip install fastapi uvicorn
+COPY requirements.txt .
 
-CMD ["uvicorn", "api.routes:app", "--host", "0.0.0.0", "--port", "8000", "--reload"]
\ No newline at end of file
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY . .
+
+CMD ["uvicorn", "api.main:app", "--host", "0.0.0.0", "--port", "8000", "--reload"]
diff --git a/backend/api/database/mongodb.py b/backend/api/database/mongodb.py
new file mode 100644
index 0000000..fbe5848
--- /dev/null
+++ b/backend/api/database/mongodb.py
@@ -0,0 +1,9 @@
+from motor.motor_asyncio import AsyncIOMotorClient
+
+MONGO_URL = "mongodb://mongo:27017"
+DB_NAME = "deckofcards"
+
+client = AsyncIOMotorClient(MONGO_URL)
+db = client[DB_NAME]
+
+users_collection = db["users"]
diff --git a/backend/api/main.py b/backend/api/main.py
index f7df1ae..1edd7e5 100644
--- a/backend/api/main.py
+++ b/backend/api/main.py
@@ -1,14 +1,26 @@
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
+from contextlib import asynccontextmanager
+from api.database.mongodb import db
 
-from routers.value_function import router as value_router
-from routers.docmf_build import router as docmf_build_router
-from routers.docmf_evaluate import router as docmf_eval_router
-from routers.docmf_simple_validation import router as simple_validation_router
-from routers.docmf_validation import router as validation_router
+# Routers
+from api.routers.test_mongo import router as test_mongo_router
+from api.routers.value_function import router as value_router
+from api.routers.docmf_build import router as docmf_build_router
+from api.routers.docmf_evaluate import router as docmf_eval_router
+from api.routers.docmf_simple_validation import router as simple_validation_router
+from api.routers.docmf_validation import router as validation_router
+from api.routers.auth import router as auth_router
+from api.routers.history import router as history_router
+from api.routers.test_mongo import router as test_mongo_router
 
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    # Aquí podrías hacer comprobaciones si quieres
+    yield
+    # No hace falta cerrar nada con Motor
 
-app = FastAPI()
+app = FastAPI(lifespan=lifespan)
 
 app.add_middleware(
     CORSMiddleware,
@@ -18,8 +30,12 @@ app.add_middleware(
     allow_headers=["*"],
 )
 
+app.include_router(test_mongo_router, prefix="/api")
 app.include_router(value_router, prefix="/api/criteria/doc")
 app.include_router(docmf_build_router, prefix="/api/criteria/doc-mf")
 app.include_router(docmf_eval_router, prefix="/api/criteria/doc-mf")
 app.include_router(simple_validation_router, prefix="/api/criteria/doc-mf")
 app.include_router(validation_router, prefix="/api/criteria/doc-mf")
+app.include_router(test_mongo_router, prefix="/api")
+app.include_router(auth_router, prefix="/api")
+app.include_router(history_router, prefix="/api")
\ No newline at end of file
diff --git a/backend/api/models/user_models.py b/backend/api/models/user_models.py
new file mode 100644
index 0000000..c611c6f
--- /dev/null
+++ b/backend/api/models/user_models.py
@@ -0,0 +1,44 @@
+from typing import List, Optional
+from pydantic import BaseModel, EmailStr, Field
+from datetime import datetime
+
+
+class FuzzyTerm(BaseModel):
+    term: str
+    core: List[float]
+    support: List[float]
+    left_nodes: List[List[float]]
+    right_nodes: List[List[float]]
+
+
+class HistoryItem(BaseModel):
+    id: Optional[str] = Field(default=None, alias="_id")
+    name: str
+    created_at: datetime
+    results: List[FuzzyTerm]
+
+
+class HistoryCreateRequest(BaseModel):
+    name: str
+    results: List[FuzzyTerm]
+
+
+class UserCreate(BaseModel):
+    username: str
+    email: EmailStr
+    password: str
+
+
+class UserLogin(BaseModel):
+    email: EmailStr
+    password: str
+
+
+class UserInDB(BaseModel):
+    id: Optional[str] = Field(default=None, alias="_id")
+    username: str
+    email: EmailStr
+    password_hash: str
+    token: Optional[str] = None
+    history: List[HistoryItem] = []
+
diff --git a/backend/api/routers/auth.py b/backend/api/routers/auth.py
new file mode 100644
index 0000000..2287379
--- /dev/null
+++ b/backend/api/routers/auth.py
@@ -0,0 +1,89 @@
+from fastapi import APIRouter, HTTPException, status
+from api.database.mongodb import users_collection
+from api.models.user_models import UserCreate, UserLogin
+from api.utils.security import hash_password, verify_password, generate_token
+from bson import ObjectId
+
+router = APIRouter(prefix="/auth", tags=["auth"])
+
+
+@router.post("/register")
+async def register_user(user: UserCreate):
+    existing_username = await users_collection.find_one({"username": user.username})
+    if existing_username:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="El nombre de usuario ya está en uso",
+        )
+
+    existing_email = await users_collection.find_one({"email": user.email})
+    if existing_email:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="El email ya está registrado",
+        )
+
+    token = generate_token()
+
+    user_doc = {
+        "username": user.username,
+        "email": user.email,
+        "password_hash": hash_password(user.password),
+        "token": token,
+        "history": [],
+    }
+
+    result = await users_collection.insert_one(user_doc)
+
+    return {
+        "message": "Usuario registrado correctamente",
+        "user_id": str(result.inserted_id),
+        "token": token,
+    }
+
+
+@router.post("/login")
+async def login_user(credentials: UserLogin):
+    user = await users_collection.find_one({"email": credentials.email})
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Credenciales inválidas",
+        )
+
+    if not verify_password(credentials.password, user["password_hash"]):
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Credenciales inválidas",
+        )
+
+    new_token = generate_token()
+
+    await users_collection.update_one(
+        {"_id": user["_id"]},
+        {"$set": {"token": new_token}}
+    )
+
+    return {
+        "message": "Login correcto",
+        "user_id": str(user["_id"]),
+        "username": user["username"],
+        "token": new_token,
+    }
+
+
+@router.post("/logout/{user_id}")
+async def logout_user(user_id: str):
+    user = await users_collection.find_one({"_id": ObjectId(user_id)})
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Usuario no encontrado",
+        )
+
+    await users_collection.update_one(
+        {"_id": ObjectId(user_id)},
+        {"$set": {"token": None}}
+    )
+
+    return {"message": "Sesión cerrada correctamente"}
diff --git a/backend/api/routers/docmf_build.py b/backend/api/routers/docmf_build.py
index 3fc355f..24467c4 100644
--- a/backend/api/routers/docmf_build.py
+++ b/backend/api/routers/docmf_build.py
@@ -1,6 +1,6 @@
 from fastapi import APIRouter, HTTPException
-from models.docmf_models import DoCMFMultiRequest
-from services.docmf_build_service import build_docmf_multi
+from api.models.docmf_models import DoCMFMultiRequest
+from api.services.docmf_build_service import build_docmf_multi
 
 router = APIRouter()
 
diff --git a/backend/api/routers/docmf_evaluate.py b/backend/api/routers/docmf_evaluate.py
index f2aae4a..3024fe8 100644
--- a/backend/api/routers/docmf_evaluate.py
+++ b/backend/api/routers/docmf_evaluate.py
@@ -1,6 +1,6 @@
 from fastapi import APIRouter, HTTPException
-from models.evaluation_models import EvaluationRequest
-from services.docmf_evaluate_service import evaluate_docmf
+from api.models.evaluation_models import EvaluationRequest
+from api.services.docmf_evaluate_service import evaluate_docmf
 
 router = APIRouter()
 
diff --git a/backend/api/routers/docmf_simple_validation.py b/backend/api/routers/docmf_simple_validation.py
index 800ec93..425384a 100644
--- a/backend/api/routers/docmf_simple_validation.py
+++ b/backend/api/routers/docmf_simple_validation.py
@@ -1,6 +1,6 @@
 from fastapi import APIRouter, HTTPException
-from models.docmf_simple_validation_models import SimpleValidationRequest
-from services.docmf_simple_validation_service import validate_simple_levels
+from api.models.docmf_simple_validation_models import SimpleValidationRequest
+from api.services.docmf_simple_validation_service import validate_simple_levels
 
 router = APIRouter()
 
diff --git a/backend/api/routers/docmf_validation.py b/backend/api/routers/docmf_validation.py
index a1bb518..92eda8d 100644
--- a/backend/api/routers/docmf_validation.py
+++ b/backend/api/routers/docmf_validation.py
@@ -1,6 +1,6 @@
 from fastapi import APIRouter, HTTPException
-from models.docmf_validation_models import ValidationRequest
-from services.docmf_validation_service import validate_levels
+from api.models.docmf_validation_models import ValidationRequest
+from api.services.docmf_validation_service import validate_levels
 
 router = APIRouter()
 
diff --git a/backend/api/routers/history.py b/backend/api/routers/history.py
new file mode 100644
index 0000000..fadd769
--- /dev/null
+++ b/backend/api/routers/history.py
@@ -0,0 +1,62 @@
+from fastapi import APIRouter, HTTPException, status
+from typing import List
+from datetime import datetime
+from bson import ObjectId
+
+from api.database.mongodb import users_collection
+from api.models.user_models import FuzzyTerm, HistoryCreateRequest
+
+router = APIRouter(prefix="/history", tags=["history"])
+
+
+@router.post("/{user_id}/add")
+async def add_history_item(user_id: str, data: HistoryCreateRequest):
+    user = await users_collection.find_one({"_id": ObjectId(user_id)})
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Usuario no encontrado",
+        )
+
+    history_item_id = ObjectId()
+
+    history_item = {
+        "_id": history_item_id,
+        "name": data.name,  # ← nuevo campo
+        "created_at": datetime.utcnow(),
+        "results": [r.dict() for r in data.results],
+    }
+
+    await users_collection.update_one(
+        {"_id": ObjectId(user_id)},
+        {"$push": {"history": history_item}},
+    )
+
+    return {
+        "message": "Elemento añadido al historial",
+        "history_item_id": str(history_item_id),
+    }
+
+
+
+@router.delete("/{user_id}/delete/{history_item_id}")
+async def delete_history_item(user_id: str, history_item_id: str):
+    user = await users_collection.find_one({"_id": ObjectId(user_id)})
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Usuario no encontrado",
+        )
+
+    result = await users_collection.update_one(
+        {"_id": ObjectId(user_id)},
+        {"$pull": {"history": {"_id": ObjectId(history_item_id)}}},
+    )
+
+    if result.modified_count == 0:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Elemento de historial no encontrado",
+        )
+
+    return {"message": "Elemento eliminado del historial"}
diff --git a/backend/api/routers/test_mongo.py b/backend/api/routers/test_mongo.py
new file mode 100644
index 0000000..43dd15d
--- /dev/null
+++ b/backend/api/routers/test_mongo.py
@@ -0,0 +1,12 @@
+from fastapi import APIRouter
+from api.database.mongodb import db
+
+router = APIRouter()
+
+@router.get("/test-mongo")
+async def test_mongo():
+    try:
+        await db.command("ping")
+        return {"status": "ok", "message": "Conexión a MongoDB correcta"}
+    except Exception as e:
+        return {"status": "error", "message": str(e)}
diff --git a/backend/api/routers/value_function.py b/backend/api/routers/value_function.py
index c30022e..0dfc5a4 100644
--- a/backend/api/routers/value_function.py
+++ b/backend/api/routers/value_function.py
@@ -1,6 +1,6 @@
 from fastapi import APIRouter, HTTPException
-from models.value_function_models import ValueFunctionRequest
-from services.value_function_service import compute_value_function, compute_points
+from api.models.value_function_models import ValueFunctionRequest
+from api.services.value_function_service import compute_value_function, compute_points
 
 router = APIRouter()
 
diff --git a/backend/api/services/docmf_evaluate_service.py b/backend/api/services/docmf_evaluate_service.py
index 37a3562..5b31eb0 100644
--- a/backend/api/services/docmf_evaluate_service.py
+++ b/backend/api/services/docmf_evaluate_service.py
@@ -1,4 +1,4 @@
-from utils.interpolation import linear_interpolation
+from api.utils.interpolation import linear_interpolation
 
 def evaluate_docmf(request):
     x = request.x
diff --git a/backend/api/utils/security.py b/backend/api/utils/security.py
new file mode 100644
index 0000000..6dd73c5
--- /dev/null
+++ b/backend/api/utils/security.py
@@ -0,0 +1,16 @@
+import secrets
+from passlib.context import CryptContext
+
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+
+
+def hash_password(password: str) -> str:
+    return pwd_context.hash(password)
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    return pwd_context.verify(plain_password, hashed_password)
+
+
+def generate_token() -> str:
+    return secrets.token_hex(32)  # 64 caracteres seguros
diff --git a/backend/requirements.txt b/backend/requirements.txt
new file mode 100644
index 0000000..26ebe6e
--- /dev/null
+++ b/backend/requirements.txt
@@ -0,0 +1,7 @@
+fastapi
+uvicorn
+motor
+pydantic
+passlib
+bcrypt==4.0.1
+email-validator
diff --git a/docker-compose.yaml b/docker-compose.yaml
index 2d3b0f5..f0fa360 100644
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -11,12 +11,6 @@ services:
       - ./backend:/app
     depends_on:
       - db
-    environment:
-      DB_HOST: db
-      DB_PORT: 3306
-      DB_USER: root
-      DB_PASSWORD: root
-      DB_NAME: deckofcards
 
   frontend:
     build:
@@ -29,16 +23,13 @@ services:
       - /app/node_modules
 
   db:
-    image: mysql:8.0
-    container_name: mysql_db
+    image: mongo:6
+    container_name: mongo
     restart: always
-    environment:
-      MYSQL_ROOT_PASSWORD: root
-      MYSQL_DATABASE: deckofcards
     ports:
-      - "3306:3306"
+      - "27018:27017"
     volumes:
-      - mysql_data:/var/lib/mysql
+      - mongo_data:/data/db
 
 volumes:
-  mysql_data:
\ No newline at end of file
+  mongo_data: