diff --git a/Makefile b/Makefile
index facda8b..1840953 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@ help: ## Show this help message
 
 install: ## Install dependencies
 	@echo "Installing backend dependencies..."
-	cd backend && python -m venv venv
+	cd backend && python3 -m venv venv
 	. backend/venv/bin/activate && pip install -r backend/requirements/dev.txt
 	@echo "Installing frontend dependencies..."
 	cd frontend && npm install
@@ -88,27 +88,6 @@ test-backend-product: ## Run backend product tests only
 test-backend-order: ## Run backend order tests only
 	cd backend && . venv/bin/activate && pytest -m order
 
-test-backend-watch: ## Run backend tests in watch mode (auto-rerun on changes)
-	cd backend && . venv/bin/activate && pip install pytest-watch && pytest-watch
-
-test-backend-parallel: ## Run backend tests in parallel (faster)
-	cd backend && . venv/bin/activate && pip install pytest-xdist && pytest -n auto
-
-test-backend-coverage-report: ## Open backend coverage report in browser
-	cd backend && . venv/bin/activate && pytest --cov=app --cov-report=html && python -m webbrowser htmlcov/index.html
-
-test-backend-failed: ## Re-run only failed backend tests
-	cd backend && . venv/bin/activate && pytest --lf
-
-test-backend-last-failed: ## Run the tests that failed in the last run
-	cd backend && . venv/bin/activate && pytest --lf
-
-test-backend-specific: ## Run specific backend test (usage: make test-backend-specific TEST=test_models.py)
-	cd backend && . venv/bin/activate && pytest tests/$(TEST)
-
-test-backend-marker: ## Run backend tests by marker (usage: make test-backend-marker MARKER=auth)
-	cd backend && . venv/bin/activate && pytest -m $(MARKER)
-
 test-frontend: ## Run frontend tests only
 	cd frontend && npm test
 
diff --git a/backend/.env.example b/backend/.env.example
index 916ff93..d0b6be8 100644
--- a/backend/.env.example
+++ b/backend/.env.example
@@ -2,7 +2,7 @@ FLASK_ENV=dev
 SECRET_KEY=your-secret-key-here
 JWT_SECRET_KEY=your-jwt-secret-key-here
 CORS_ORIGINS=*
-DEV_DATABASE_URL=postgresql://crafting:devpassword@localhost:5432/crafting_shop
+DATABASE_URL=postgresql://crafting:devpassword@localhost:5432/crafting_shop
 DATABASE_URL=postgresql://user:password@localhost/proddb
 TEST_DATABASE_URL=sqlite:///test.db
 
diff --git a/backend/app/__init__.py b/backend/app/__init__.py
index df448d6..667020f 100644
--- a/backend/app/__init__.py
+++ b/backend/app/__init__.py
@@ -49,13 +49,27 @@ def create_app(config_name=None):
     init_celery(app)
 
     # Import models (required for migrations)
-    from app.models import order, product, user  # noqa: F401
+    from app.models import (
+        board,
+        card,
+        card_label,
+        check_item,
+        checklist,
+        comment,
+        label,
+        list_model,
+        order,
+        product,
+        user,
+    )  # noqa: F401
 
     # Register blueprints
     from app.routes import api_bp, health_bp
+    from app.routes.kanban import kanban_bp
 
     app.register_blueprint(api_bp, url_prefix="/api")
     app.register_blueprint(health_bp)
+    app.register_blueprint(kanban_bp, url_prefix="/api")
 
     # Global error handlers
     @app.errorhandler(404)
diff --git a/backend/app/config.py b/backend/app/config.py
index 69fc836..be03ff3 100644
--- a/backend/app/config.py
+++ b/backend/app/config.py
@@ -30,20 +30,28 @@ class Config:
         "worker_max_tasks_per_child": 100,
         "broker_connection_retry_on_startup": True,
     }
+    
+    SQLALCHEMY_ENGINE_OPTIONS = {
+        'pool_size': 5,  # Reduce from default
+        'max_overflow': 2,  # Reduce overflow
+        'pool_timeout': 30,
+        'pool_recycle': 1800,  # Recycle connections after 30 minutes
+        'pool_pre_ping': True,  # Verify connections before using
+    }
 
 
 class DevelopmentConfig(Config):
     """Development configuration"""
 
     DEBUG = True
-    SQLALCHEMY_DATABASE_URI = os.environ.get("DEV_DATABASE_URL") or "sqlite:///dev.db"
+    SQLALCHEMY_DATABASE_URI = os.environ["DATABASE_URL"]
 
 
 class TestingConfig(Config):
     """Testing configuration"""
 
     TESTING = True
-    SQLALCHEMY_DATABASE_URI = os.environ.get("TEST_DATABASE_URL") or "sqlite:///test.db"
+    SQLALCHEMY_DATABASE_URI = "postgresql://kanban:devpassword@localhost:5451/kanban_test"
     WTF_CSRF_ENABLED = False
 
 
@@ -51,9 +59,7 @@ class ProductionConfig(Config):
     """Production configuration"""
 
     DEBUG = False
-    SQLALCHEMY_DATABASE_URI = (
-        os.environ.get("DATABASE_URL") or "postgresql://user:password@localhost/proddb"
-    )
+    SQLALCHEMY_DATABASE_URI = os.environ["DATABASE_URL"]
 
     # Security headers
     SESSION_COOKIE_SECURE = True
diff --git a/backend/app/models/__init__.py b/backend/app/models/__init__.py
index 713196e..746547b 100644
--- a/backend/app/models/__init__.py
+++ b/backend/app/models/__init__.py
@@ -1,5 +1,26 @@
+from app.models.board import Board
+from app.models.card import Card
+from app.models.card_label import CardLabel
+from app.models.check_item import CheckItem
+from app.models.checklist import Checklist
+from app.models.comment import Comment
+from app.models.label import Label
+from app.models.list_model import List
 from app.models.order import Order, OrderItem
 from app.models.product import Product
 from app.models.user import User
 
-__all__ = ["User", "Product", "Order", "OrderItem"]
+__all__ = [
+    "User",
+    "Product",
+    "Order",
+    "OrderItem",
+    "Board",
+    "List",
+    "Card",
+    "Label",
+    "CardLabel",
+    "Checklist",
+    "CheckItem",
+    "Comment",
+]
diff --git a/backend/app/models/board.py b/backend/app/models/board.py
new file mode 100644
index 0000000..92f3c12
--- /dev/null
+++ b/backend/app/models/board.py
@@ -0,0 +1,64 @@
+from datetime import UTC, datetime
+from sqlalchemy.dialects.postgresql import JSONB
+
+from app import db
+
+
+class Board(db.Model):
+    """Board model for Kanban boards"""
+
+    __tablename__ = "boards"
+
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(200), nullable=False, index=True)
+    description = db.Column(db.Text)
+    closed = db.Column(db.Boolean, default=False, index=True)
+    url = db.Column(db.String(500))
+    short_link = db.Column(db.String(10), unique=True)
+    short_url = db.Column(db.String(500))
+
+    # Foreign keys
+    user_id = db.Column(db.Integer, db.ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
+
+    # Timestamps
+    date_last_activity = db.Column(db.DateTime)
+    date_last_view = db.Column(db.DateTime)
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    # JSON fields for complex data
+    prefs = db.Column(JSONB)  # board preferences
+    label_names = db.Column(JSONB)  # label color mappings
+    limits = db.Column(JSONB)  # various limits
+
+    # Relationships
+    lists = db.relationship("List", backref="board", cascade="all, delete-orphan", lazy="dynamic")
+    cards = db.relationship("Card", backref="board", cascade="all, delete-orphan", lazy="dynamic")
+    labels = db.relationship("Label", backref="board", cascade="all, delete-orphan", lazy="dynamic")
+
+    def to_dict(self):
+        """Convert board to dictionary"""
+        return {
+            "id": self.id,
+            "name": self.name,
+            "description": self.description,
+            "closed": self.closed,
+            "url": self.url,
+            "short_link": self.short_link,
+            "short_url": self.short_url,
+            "user_id": self.user_id,
+            "date_last_activity": self.date_last_activity.isoformat() if self.date_last_activity else None,
+            "date_last_view": self.date_last_view.isoformat() if self.date_last_view else None,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+            "prefs": self.prefs,
+            "label_names": self.label_names,
+            "limits": self.limits,
+        }
+
+    def __repr__(self):
+        return f"<Board {self.name}>"
\ No newline at end of file
diff --git a/backend/app/models/card.py b/backend/app/models/card.py
new file mode 100644
index 0000000..b4d5568
--- /dev/null
+++ b/backend/app/models/card.py
@@ -0,0 +1,66 @@
+from datetime import UTC, datetime
+from sqlalchemy.dialects.postgresql import JSONB
+
+from app import db
+
+
+class Card(db.Model):
+    """Card model for Kanban cards"""
+
+    __tablename__ = "cards"
+
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(200), nullable=False)
+    description = db.Column(db.Text)
+    closed = db.Column(db.Boolean, default=False)
+    due = db.Column(db.DateTime)
+    due_complete = db.Column(db.Boolean, default=False)
+    pos = db.Column(db.Float)  # position for sorting
+    id_short = db.Column(db.Integer)  # short ID for URLs
+
+    # Foreign keys
+    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
+    list_id = db.Column(db.Integer, db.ForeignKey("lists.id", ondelete="CASCADE"), nullable=False, index=True)
+
+    # Timestamps
+    date_last_activity = db.Column(db.DateTime)
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    # JSON fields
+    badges = db.Column(JSONB)  # card badges/stats
+    cover = db.Column(JSONB)  # cover settings
+    desc_data = db.Column(JSONB)
+
+    # Relationships
+    checklists = db.relationship("Checklist", backref="card", cascade="all, delete-orphan", lazy="dynamic")
+    labels = db.relationship("CardLabel", backref="card", cascade="all, delete-orphan", lazy="dynamic")
+    comments = db.relationship("Comment", backref="card", cascade="all, delete-orphan", lazy="dynamic")
+
+    def to_dict(self):
+        """Convert card to dictionary"""
+        return {
+            "id": self.id,
+            "name": self.name,
+            "description": self.description,
+            "closed": self.closed,
+            "due": self.due.isoformat() if self.due else None,
+            "due_complete": self.due_complete,
+            "pos": self.pos,
+            "id_short": self.id_short,
+            "board_id": self.board_id,
+            "list_id": self.list_id,
+            "date_last_activity": self.date_last_activity.isoformat() if self.date_last_activity else None,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+            "badges": self.badges,
+            "cover": self.cover,
+            "desc_data": self.desc_data,
+        }
+
+    def __repr__(self):
+        return f"<Card {self.name}>"
\ No newline at end of file
diff --git a/backend/app/models/card_label.py b/backend/app/models/card_label.py
new file mode 100644
index 0000000..f4c49c3
--- /dev/null
+++ b/backend/app/models/card_label.py
@@ -0,0 +1,31 @@
+from datetime import UTC, datetime
+
+from app import db
+
+
+class CardLabel(db.Model):
+    """Many-to-many relationship between cards and labels"""
+
+    __tablename__ = "card_labels"
+
+    id = db.Column(db.Integer, primary_key=True)
+    card_id = db.Column(db.Integer, db.ForeignKey("cards.id", ondelete="CASCADE"), nullable=False, index=True)
+    label_id = db.Column(db.Integer, db.ForeignKey("labels.id", ondelete="CASCADE"), nullable=False, index=True)
+
+    # Timestamps
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+
+    # Unique constraint to prevent duplicate associations
+    __table_args__ = (db.UniqueConstraint("card_id", "label_id", name="_card_label_uc"),)
+
+    def to_dict(self):
+        """Convert card label to dictionary"""
+        return {
+            "id": self.id,
+            "card_id": self.card_id,
+            "label_id": self.label_id,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+        }
+
+    def __repr__(self):
+        return f"<CardLabel card_id={self.card_id} label_id={self.label_id}>"
\ No newline at end of file
diff --git a/backend/app/models/check_item.py b/backend/app/models/check_item.py
new file mode 100644
index 0000000..dcbe712
--- /dev/null
+++ b/backend/app/models/check_item.py
@@ -0,0 +1,44 @@
+from datetime import UTC, datetime
+
+from app import db
+
+
+class CheckItem(db.Model):
+    """CheckItem model for checklist items"""
+
+    __tablename__ = "check_items"
+
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(500), nullable=False)
+    pos = db.Column(db.Float)  # position for sorting
+    state = db.Column(db.String(20), default="incomplete")  # 'complete' or 'incomplete'
+    due = db.Column(db.DateTime)
+
+    # Foreign keys
+    checklist_id = db.Column(db.Integer, db.ForeignKey("checklists.id", ondelete="CASCADE"), nullable=False, index=True)
+    user_id = db.Column(db.Integer, db.ForeignKey("users.id"), nullable=True, index=True)
+
+    # Timestamps
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    def to_dict(self):
+        """Convert check item to dictionary"""
+        return {
+            "id": self.id,
+            "name": self.name,
+            "pos": self.pos,
+            "state": self.state,
+            "due": self.due.isoformat() if self.due else None,
+            "checklist_id": self.checklist_id,
+            "user_id": self.user_id,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+    def __repr__(self):
+        return f"<CheckItem {self.name} ({self.state})>"
\ No newline at end of file
diff --git a/backend/app/models/checklist.py b/backend/app/models/checklist.py
new file mode 100644
index 0000000..f04197a
--- /dev/null
+++ b/backend/app/models/checklist.py
@@ -0,0 +1,43 @@
+from datetime import UTC, datetime
+
+from app import db
+
+
+class Checklist(db.Model):
+    """Checklist model for Kanban checklists"""
+
+    __tablename__ = "checklists"
+
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(200), nullable=False)
+    pos = db.Column(db.Float)  # position for sorting
+
+    # Foreign keys
+    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
+    card_id = db.Column(db.Integer, db.ForeignKey("cards.id", ondelete="CASCADE"), nullable=False, index=True)
+
+    # Timestamps
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    # Relationships
+    check_items = db.relationship("CheckItem", backref="checklist", cascade="all, delete-orphan", lazy="dynamic")
+
+    def to_dict(self):
+        """Convert checklist to dictionary"""
+        return {
+            "id": self.id,
+            "name": self.name,
+            "pos": self.pos,
+            "board_id": self.board_id,
+            "card_id": self.card_id,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+    def __repr__(self):
+        return f"<Checklist {self.name}>"
\ No newline at end of file
diff --git a/backend/app/models/comment.py b/backend/app/models/comment.py
new file mode 100644
index 0000000..bd873d1
--- /dev/null
+++ b/backend/app/models/comment.py
@@ -0,0 +1,38 @@
+from datetime import UTC, datetime
+
+from app import db
+
+
+class Comment(db.Model):
+    """Comment model for card comments"""
+
+    __tablename__ = "comments"
+
+    id = db.Column(db.Integer, primary_key=True)
+    text = db.Column(db.Text, nullable=False)
+
+    # Foreign keys
+    card_id = db.Column(db.Integer, db.ForeignKey("cards.id", ondelete="CASCADE"), nullable=False, index=True)
+    user_id = db.Column(db.Integer, db.ForeignKey("users.id"), nullable=False, index=True)
+
+    # Timestamps
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    def to_dict(self):
+        """Convert comment to dictionary"""
+        return {
+            "id": self.id,
+            "text": self.text,
+            "card_id": self.card_id,
+            "user_id": self.user_id,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+    def __repr__(self):
+        return f"<Comment id={self.id} card_id={self.card_id}>"
\ No newline at end of file
diff --git a/backend/app/models/label.py b/backend/app/models/label.py
new file mode 100644
index 0000000..0bdb205
--- /dev/null
+++ b/backend/app/models/label.py
@@ -0,0 +1,43 @@
+from datetime import UTC, datetime
+
+from app import db
+
+
+class Label(db.Model):
+    """Label model for Kanban labels"""
+
+    __tablename__ = "labels"
+
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(100))
+    color = db.Column(db.String(50))  # color name like 'green', 'red', 'blue'
+    uses = db.Column(db.Integer, default=0)
+
+    # Foreign keys
+    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
+
+    # Timestamps
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    # Relationships
+    card_labels = db.relationship("CardLabel", backref="label", cascade="all, delete-orphan", lazy="dynamic")
+
+    def to_dict(self):
+        """Convert label to dictionary"""
+        return {
+            "id": self.id,
+            "name": self.name,
+            "color": self.color,
+            "uses": self.uses,
+            "board_id": self.board_id,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+    def __repr__(self):
+        return f"<Label {self.name} ({self.color})>"
\ No newline at end of file
diff --git a/backend/app/models/list_model.py b/backend/app/models/list_model.py
new file mode 100644
index 0000000..2127e25
--- /dev/null
+++ b/backend/app/models/list_model.py
@@ -0,0 +1,43 @@
+from datetime import UTC, datetime
+
+from app import db
+
+
+class List(db.Model):
+    """List model for Kanban lists (columns)"""
+
+    __tablename__ = "lists"
+
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(200), nullable=False)
+    closed = db.Column(db.Boolean, default=False)
+    pos = db.Column(db.Float)  # position for sorting
+
+    # Foreign keys
+    board_id = db.Column(db.Integer, db.ForeignKey("boards.id", ondelete="CASCADE"), nullable=False, index=True)
+
+    # Timestamps
+    created_at = db.Column(db.DateTime, default=lambda: datetime.now(UTC))
+    updated_at = db.Column(
+        db.DateTime,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    # Relationships
+    cards = db.relationship("Card", backref="list", cascade="all, delete-orphan", lazy="dynamic")
+
+    def to_dict(self):
+        """Convert list to dictionary"""
+        return {
+            "id": self.id,
+            "name": self.name,
+            "closed": self.closed,
+            "pos": self.pos,
+            "board_id": self.board_id,
+            "created_at": self.created_at.isoformat() if self.created_at else None,
+            "updated_at": self.updated_at.isoformat() if self.updated_at else None,
+        }
+
+    def __repr__(self):
+        return f"<List {self.name}>"
\ No newline at end of file
diff --git a/backend/app/models/user.py b/backend/app/models/user.py
index 72fbcdc..07c5621 100644
--- a/backend/app/models/user.py
+++ b/backend/app/models/user.py
@@ -27,6 +27,7 @@ class User(db.Model):
 
     # Relationships
     orders = db.relationship("Order", back_populates="user", lazy="dynamic")
+    boards = db.relationship("Board", backref="user", cascade="all, delete-orphan", lazy="dynamic")
 
     def set_password(self, password):
         """Hash and set password"""
diff --git a/backend/app/routes/kanban.py b/backend/app/routes/kanban.py
new file mode 100644
index 0000000..c7ab45c
--- /dev/null
+++ b/backend/app/routes/kanban.py
@@ -0,0 +1,726 @@
+from datetime import UTC, datetime
+from flask import Blueprint, jsonify, request
+from flask_jwt_extended import jwt_required, get_jwt_identity
+
+from app import db
+from app.models import (
+    Board,
+    Card,
+    CardLabel,
+    CheckItem,
+    Checklist,
+    Comment,
+    Label,
+    List,
+    User,
+)
+
+kanban_bp = Blueprint("kanban", __name__)
+
+# =============================================================================
+# BOARD ROUTES
+# =============================================================================
+
+
+@kanban_bp.route("/boards", methods=["GET"])
+@jwt_required()
+def get_boards():
+    """Get all boards for current user"""
+    user_id = int(get_jwt_identity())
+    boards = Board.query.filter_by(user_id=user_id).all()
+    return jsonify([board.to_dict() for board in boards]), 200
+
+
+@kanban_bp.route("/boards/<int:board_id>", methods=["GET"])
+@jwt_required()
+def get_board(board_id):
+    """Get a single board with all its details"""
+    user_id = int(get_jwt_identity())
+    board = db.session.get(Board, board_id)
+
+    if not board:
+        return jsonify({"error": "Board not found"}), 404
+
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    # Get all lists for this board
+    lists_data = []
+    for lst in board.lists.filter_by(closed=False).order_by(List.pos).all():
+        cards_data = []
+        for card in lst.cards.filter_by(closed=False).order_by(Card.pos).all():
+            card_dict = card.to_dict()
+            # Add labels for this card
+            card_dict["labels"] = [
+                label.to_dict()
+                for label in (
+                    db.session.query(Label)
+                    .join(CardLabel)
+                    .filter(CardLabel.card_id == card.id)
+                    .all()
+                )
+            ]
+            cards_data.append(card_dict)
+
+        lists_data.append({**lst.to_dict(), "cards": cards_data})
+
+    board_dict = board.to_dict()
+    board_dict["lists"] = lists_data
+    board_dict["labels"] = [label.to_dict() for label in board.labels.all()]
+
+    return jsonify(board_dict), 200
+
+
+@kanban_bp.route("/boards", methods=["POST"])
+@jwt_required()
+def create_board():
+    """Create a new board"""
+    user_id = int(get_jwt_identity())
+    data = request.get_json()
+
+    if not data or not data.get("name"):
+        return jsonify({"error": "Board name is required"}), 400
+
+    board = Board(
+        name=data["name"],
+        description=data.get("description"),
+        user_id=user_id,
+        url=data.get("url"),
+        short_link=data.get("short_link"),
+        short_url=data.get("short_url"),
+        prefs=data.get("prefs"),
+        label_names=data.get("label_names"),
+        limits=data.get("limits"),
+    )
+
+    db.session.add(board)
+    db.session.commit()
+
+    return jsonify(board.to_dict()), 201
+
+
+@kanban_bp.route("/boards/<int:board_id>", methods=["PUT"])
+@jwt_required()
+def update_board(board_id):
+    """Update a board"""
+    user_id = int(get_jwt_identity())
+    board = db.session.get(Board, board_id)
+
+    if not board:
+        return jsonify({"error": "Board not found"}), 404
+
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    board.name = data.get("name", board.name)
+    board.description = data.get("description", board.description)
+    board.closed = data.get("closed", board.closed)
+    board.url = data.get("url", board.url)
+    board.short_url = data.get("short_url", board.short_url)
+    board.prefs = data.get("prefs", board.prefs)
+    board.label_names = data.get("label_names", board.label_names)
+    board.limits = data.get("limits", board.limits)
+    board.date_last_activity = datetime.now(UTC)
+
+    db.session.commit()
+
+    return jsonify(board.to_dict()), 200
+
+
+@kanban_bp.route("/boards/<int:board_id>", methods=["DELETE"])
+@jwt_required()
+def delete_board(board_id):
+    """Delete a board"""
+    user_id = int(get_jwt_identity())
+    board = db.session.get(Board, board_id)
+
+    if not board:
+        return jsonify({"error": "Board not found"}), 404
+
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    db.session.delete(board)
+    db.session.commit()
+
+    return jsonify({"message": "Board deleted"}), 200
+
+
+# =============================================================================
+# LIST ROUTES
+# =============================================================================
+
+
+@kanban_bp.route("/boards/<int:board_id>/lists", methods=["POST"])
+@jwt_required()
+def create_list(board_id):
+    """Create a new list in a board"""
+    user_id = int(get_jwt_identity())
+    board = db.session.get(Board, board_id)
+
+    if not board:
+        return jsonify({"error": "Board not found"}), 404
+
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    if not data or not data.get("name"):
+        return jsonify({"error": "List name is required"}), 400
+
+    lst = List(name=data["name"], board_id=board_id, pos=data.get("pos", 65535.0))
+
+    db.session.add(lst)
+    db.session.commit()
+
+    return jsonify(lst.to_dict()), 201
+
+
+@kanban_bp.route("/lists/<int:list_id>", methods=["PUT"])
+@jwt_required()
+def update_list(list_id):
+    """Update a list"""
+    user_id = int(get_jwt_identity())
+    lst = db.session.get(List, list_id)
+
+    if not lst:
+        return jsonify({"error": "List not found"}), 404
+
+    board = db.session.get(Board, lst.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    lst.name = data.get("name", lst.name)
+    lst.closed = data.get("closed", lst.closed)
+    lst.pos = data.get("pos", lst.pos)
+
+    db.session.commit()
+
+    return jsonify(lst.to_dict()), 200
+
+
+@kanban_bp.route("/lists/<int:list_id>", methods=["DELETE"])
+@jwt_required()
+def delete_list(list_id):
+    """Delete a list"""
+    user_id = int(get_jwt_identity())
+    lst = db.session.get(List, list_id)
+
+    if not lst:
+        return jsonify({"error": "List not found"}), 404
+
+    board = db.session.get(Board, lst.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    db.session.delete(lst)
+    db.session.commit()
+
+    return jsonify({"message": "List deleted"}), 200
+
+
+# =============================================================================
+# CARD ROUTES
+# =============================================================================
+
+
+@kanban_bp.route("/lists/<int:list_id>/cards", methods=["POST"])
+@jwt_required()
+def create_card(list_id):
+    """Create a new card in a list"""
+    user_id = int(get_jwt_identity())
+    lst = db.session.get(List, list_id)
+
+    if not lst:
+        return jsonify({"error": "List not found"}), 404
+
+    board = db.session.get(Board, lst.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    if not data or not data.get("name"):
+        return jsonify({"error": "Card name is required"}), 400
+
+    card = Card(
+        name=data["name"],
+        description=data.get("description"),
+        board_id=lst.board_id,
+        list_id=list_id,
+        pos=data.get("pos", 65535.0),
+        due=data.get("due"),
+        due_complete=data.get("due_complete", False),
+        badges=data.get("badges"),
+        cover=data.get("cover"),
+        desc_data=data.get("desc_data"),
+    )
+
+    # Update board activity
+    board.date_last_activity = datetime.now(UTC)
+
+    db.session.add(card)
+    db.session.commit()
+
+    return jsonify(card.to_dict()), 201
+
+
+@kanban_bp.route("/cards/<int:card_id>", methods=["GET"])
+@jwt_required()
+def get_card(card_id):
+    """Get a single card with full details"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    card_dict = card.to_dict()
+
+    # Add labels
+    card_dict["labels"] = [
+        label.to_dict()
+        for label in (
+            db.session.query(Label)
+            .join(CardLabel)
+            .filter(CardLabel.card_id == card.id)
+            .all()
+        )
+    ]
+
+    # Add checklists
+    card_dict["checklists"] = [
+        {**checklist.to_dict(), "items": [item.to_dict() for item in checklist.check_items.all()]}
+        for checklist in card.checklists.all()
+    ]
+
+    # Add comments
+    card_dict["comments"] = []
+    for comment in card.comments.all():
+        comment_dict = comment.to_dict()
+        user = db.session.get(User, comment.user_id)
+        comment_dict["user"] = user.to_dict() if user else None
+        card_dict["comments"].append(comment_dict)
+
+    return jsonify(card_dict), 200
+
+
+@kanban_bp.route("/cards/<int:card_id>", methods=["PUT"])
+@jwt_required()
+def update_card(card_id):
+    """Update a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    card.name = data.get("name", card.name)
+    card.description = data.get("description", card.description)
+    card.closed = data.get("closed", card.closed)
+    card.pos = data.get("pos", card.pos)
+    card.due = data.get("due")
+    card.due_complete = data.get("due_complete", card.due_complete)
+    card.badges = data.get("badges", card.badges)
+    card.cover = data.get("cover", card.cover)
+    card.desc_data = data.get("desc_data", card.desc_data)
+
+    # Handle moving card to different list
+    if "list_id" in data:
+        new_list_id = data["list_id"]
+        new_list = db.session.get(List, new_list_id)
+        if new_list and new_list.board_id == card.board_id:
+            card.list_id = new_list_id
+
+    card.date_last_activity = datetime.now(UTC)
+    board.date_last_activity = datetime.now(UTC)
+
+    db.session.commit()
+
+    return jsonify(card.to_dict()), 200
+
+
+@kanban_bp.route("/cards/<int:card_id>", methods=["DELETE"])
+@jwt_required()
+def delete_card(card_id):
+    """Delete a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    db.session.delete(card)
+    db.session.commit()
+
+    return jsonify({"message": "Card deleted"}), 200
+
+
+# =============================================================================
+# LABEL ROUTES
+# =============================================================================
+
+
+@kanban_bp.route("/boards/<int:board_id>/labels", methods=["GET"])
+@jwt_required()
+def get_labels(board_id):
+    """Get all labels for a board"""
+    user_id = int(get_jwt_identity())
+    board = db.session.get(Board, board_id)
+
+    if not board:
+        return jsonify({"error": "Board not found"}), 404
+
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    labels = board.labels.all()
+    return jsonify([label.to_dict() for label in labels]), 200
+
+
+@kanban_bp.route("/boards/<int:board_id>/labels", methods=["POST"])
+@jwt_required()
+def create_label(board_id):
+    """Create a new label in a board"""
+    user_id = int(get_jwt_identity())
+    board = db.session.get(Board, board_id)
+
+    if not board:
+        return jsonify({"error": "Board not found"}), 404
+
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    if not data or not data.get("name"):
+        return jsonify({"error": "Label name is required"}), 400
+
+    label = Label(
+        name=data["name"],
+        color=data.get("color"),
+        board_id=board_id,
+    )
+
+    db.session.add(label)
+    db.session.commit()
+
+    return jsonify(label.to_dict()), 201
+
+
+@kanban_bp.route("/cards/<int:card_id>/labels", methods=["POST"])
+@jwt_required()
+def add_label_to_card(card_id):
+    """Add a label to a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+    label_id = data.get("label_id")
+
+    if not label_id:
+        return jsonify({"error": "Label ID is required"}), 400
+
+    label = db.session.get(Label, label_id)
+    if not label or label.board_id != card.board_id:
+        return jsonify({"error": "Label not found or doesn't belong to this board"}), 404
+
+    # Check if already labeled
+    existing = CardLabel.query.filter_by(card_id=card_id, label_id=label_id).first()
+    if existing:
+        return jsonify({"error": "Label already added to card"}), 400
+
+    card_label = CardLabel(card_id=card_id, label_id=label_id)
+    db.session.add(card_label)
+    db.session.commit()
+
+    return jsonify(card_label.to_dict()), 201
+
+
+@kanban_bp.route("/cards/<int:card_id>/labels/<int:label_id>", methods=["DELETE"])
+@jwt_required()
+def remove_label_from_card(card_id, label_id):
+    """Remove a label from a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    card_label = CardLabel.query.filter_by(card_id=card_id, label_id=label_id).first()
+    if not card_label:
+        return jsonify({"error": "Label not found on card"}), 404
+
+    db.session.delete(card_label)
+    db.session.commit()
+
+    return jsonify({"message": "Label removed from card"}), 200
+
+
+# =============================================================================
+# CHECKLIST ROUTES
+# =============================================================================
+
+
+@kanban_bp.route("/cards/<int:card_id>/checklists", methods=["POST"])
+@jwt_required()
+def create_checklist(card_id):
+    """Create a new checklist in a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    if not data or not data.get("name"):
+        return jsonify({"error": "Checklist name is required"}), 400
+
+    checklist = Checklist(
+        name=data["name"],
+        card_id=card_id,
+        board_id=card.board_id,
+        pos=data.get("pos", 0),
+    )
+
+    db.session.add(checklist)
+    db.session.commit()
+
+    return jsonify(checklist.to_dict()), 201
+
+
+@kanban_bp.route("/checklists/<int:checklist_id>/items", methods=["POST"])
+@jwt_required()
+def create_check_item(checklist_id):
+    """Create a new check item in a checklist"""
+    user_id = int(get_jwt_identity())
+    checklist = db.session.get(Checklist, checklist_id)
+
+    if not checklist:
+        return jsonify({"error": "Checklist not found"}), 404
+
+    card = db.session.get(Card, checklist.card_id)
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    if not data or not data.get("name"):
+        return jsonify({"error": "Check item name is required"}), 400
+
+    check_item = CheckItem(
+        name=data["name"],
+        checklist_id=checklist_id,
+        pos=data.get("pos", 0),
+        state=data.get("state", "incomplete"),
+        due=data.get("due"),
+    )
+
+    db.session.add(check_item)
+    db.session.commit()
+
+    return jsonify(check_item.to_dict()), 201
+
+
+@kanban_bp.route("/check-items/<int:item_id>", methods=["PUT"])
+@jwt_required()
+def update_check_item(item_id):
+    """Update a check item"""
+    user_id = int(get_jwt_identity())
+    check_item = db.session.get(CheckItem, item_id)
+
+    if not check_item:
+        return jsonify({"error": "Check item not found"}), 404
+
+    checklist = db.session.get(Checklist, check_item.checklist_id)
+    card = db.session.get(Card, checklist.card_id)
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    check_item.name = data.get("name", check_item.name)
+    check_item.state = data.get("state", check_item.state)
+    check_item.pos = data.get("pos", check_item.pos)
+    check_item.due = data.get("due")
+
+    db.session.commit()
+
+    return jsonify(check_item.to_dict()), 200
+
+
+@kanban_bp.route("/checklists/<int:checklist_id>", methods=["DELETE"])
+@jwt_required()
+def delete_checklist(checklist_id):
+    """Delete a checklist"""
+    user_id = int(get_jwt_identity())
+    checklist = db.session.get(Checklist, checklist_id)
+
+    if not checklist:
+        return jsonify({"error": "Checklist not found"}), 404
+
+    card = db.session.get(Card, checklist.card_id)
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    db.session.delete(checklist)
+    db.session.commit()
+
+    return jsonify({"message": "Checklist deleted"}), 200
+
+
+@kanban_bp.route("/check-items/<int:item_id>", methods=["DELETE"])
+@jwt_required()
+def delete_check_item(item_id):
+    """Delete a check item"""
+    user_id = int(get_jwt_identity())
+    check_item = db.session.get(CheckItem, item_id)
+
+    if not check_item:
+        return jsonify({"error": "Check item not found"}), 404
+
+    checklist = db.session.get(Checklist, check_item.checklist_id)
+    card = db.session.get(Card, checklist.card_id)
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    db.session.delete(check_item)
+    db.session.commit()
+
+    return jsonify({"message": "Check item deleted"}), 200
+
+
+# =============================================================================
+# COMMENT ROUTES
+# =============================================================================
+
+
+@kanban_bp.route("/cards/<int:card_id>/comments", methods=["GET"])
+@jwt_required()
+def get_comments(card_id):
+    """Get all comments for a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    comments = []
+    for comment in card.comments.order_by(Comment.created_at.desc()).all():
+        comment_dict = comment.to_dict()
+        user = db.session.get(User, comment.user_id)
+        comment_dict["user"] = user.to_dict() if user else None
+        comments.append(comment_dict)
+
+    return jsonify(comments), 200
+
+
+@kanban_bp.route("/cards/<int:card_id>/comments", methods=["POST"])
+@jwt_required()
+def create_comment(card_id):
+    """Create a new comment on a card"""
+    user_id = int(get_jwt_identity())
+    card = db.session.get(Card, card_id)
+
+    if not card:
+        return jsonify({"error": "Card not found"}), 404
+
+    board = db.session.get(Board, card.board_id)
+    if board.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    if not data or not data.get("text"):
+        return jsonify({"error": "Comment text is required"}), 400
+
+    comment = Comment(text=data["text"], card_id=card_id, user_id=user_id)
+
+    db.session.add(comment)
+    db.session.commit()
+
+    return jsonify(comment.to_dict()), 201
+
+
+@kanban_bp.route("/comments/<int:comment_id>", methods=["PUT"])
+@jwt_required()
+def update_comment(comment_id):
+    """Update a comment"""
+    user_id = int(get_jwt_identity())
+    comment = db.session.get(Comment, comment_id)
+
+    if not comment:
+        return jsonify({"error": "Comment not found"}), 404
+
+    if comment.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    data = request.get_json()
+
+    comment.text = data.get("text", comment.text)
+
+    db.session.commit()
+
+    return jsonify(comment.to_dict()), 200
+
+
+@kanban_bp.route("/comments/<int:comment_id>", methods=["DELETE"])
+@jwt_required()
+def delete_comment(comment_id):
+    """Delete a comment"""
+    user_id = int(get_jwt_identity())
+    comment = db.session.get(Comment, comment_id)
+
+    if not comment:
+        return jsonify({"error": "Comment not found"}), 404
+
+    if comment.user_id != user_id:
+        return jsonify({"error": "Access denied"}), 403
+
+    db.session.delete(comment)
+    db.session.commit()
+
+    return jsonify({"message": "Comment deleted"}), 200
\ No newline at end of file
diff --git a/backend/migrations/versions/1c0b9dfbd933_add_kanban_models_board_list_card_label_.py b/backend/migrations/versions/1c0b9dfbd933_add_kanban_models_board_list_card_label_.py
new file mode 100644
index 0000000..cfc4e11
--- /dev/null
+++ b/backend/migrations/versions/1c0b9dfbd933_add_kanban_models_board_list_card_label_.py
@@ -0,0 +1,206 @@
+"""Add Kanban models (Board, List, Card, Label, Checklist, Comment)
+
+Revision ID: 1c0b9dfbd933
+Revises: dd57c5299d60
+Create Date: 2026-02-25 18:50:14.709257
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+# revision identifiers, used by Alembic.
+revision = '1c0b9dfbd933'
+down_revision = 'dd57c5299d60'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('boards',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('description', sa.Text(), nullable=True),
+    sa.Column('closed', sa.Boolean(), nullable=True),
+    sa.Column('url', sa.String(length=500), nullable=True),
+    sa.Column('short_link', sa.String(length=10), nullable=True),
+    sa.Column('short_url', sa.String(length=500), nullable=True),
+    sa.Column('user_id', sa.Integer(), nullable=False),
+    sa.Column('date_last_activity', sa.DateTime(), nullable=True),
+    sa.Column('date_last_view', sa.DateTime(), nullable=True),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.Column('prefs', postgresql.JSONB(astext_type=sa.Text()), nullable=True),
+    sa.Column('label_names', postgresql.JSONB(astext_type=sa.Text()), nullable=True),
+    sa.Column('limits', postgresql.JSONB(astext_type=sa.Text()), nullable=True),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ondelete='CASCADE'),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('short_link')
+    )
+    with op.batch_alter_table('boards', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_boards_closed'), ['closed'], unique=False)
+        batch_op.create_index(batch_op.f('ix_boards_name'), ['name'], unique=False)
+        batch_op.create_index(batch_op.f('ix_boards_user_id'), ['user_id'], unique=False)
+
+    op.create_table('labels',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=100), nullable=True),
+    sa.Column('color', sa.String(length=50), nullable=True),
+    sa.Column('uses', sa.Integer(), nullable=True),
+    sa.Column('board_id', sa.Integer(), nullable=False),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.ForeignKeyConstraint(['board_id'], ['boards.id'], ondelete='CASCADE'),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('labels', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_labels_board_id'), ['board_id'], unique=False)
+
+    op.create_table('lists',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('closed', sa.Boolean(), nullable=True),
+    sa.Column('pos', sa.Float(), nullable=True),
+    sa.Column('board_id', sa.Integer(), nullable=False),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.ForeignKeyConstraint(['board_id'], ['boards.id'], ondelete='CASCADE'),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('lists', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_lists_board_id'), ['board_id'], unique=False)
+
+    op.create_table('cards',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('description', sa.Text(), nullable=True),
+    sa.Column('closed', sa.Boolean(), nullable=True),
+    sa.Column('due', sa.DateTime(), nullable=True),
+    sa.Column('due_complete', sa.Boolean(), nullable=True),
+    sa.Column('pos', sa.Float(), nullable=True),
+    sa.Column('id_short', sa.Integer(), nullable=True),
+    sa.Column('board_id', sa.Integer(), nullable=False),
+    sa.Column('list_id', sa.Integer(), nullable=False),
+    sa.Column('date_last_activity', sa.DateTime(), nullable=True),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.Column('badges', postgresql.JSONB(astext_type=sa.Text()), nullable=True),
+    sa.Column('cover', postgresql.JSONB(astext_type=sa.Text()), nullable=True),
+    sa.Column('desc_data', postgresql.JSONB(astext_type=sa.Text()), nullable=True),
+    sa.ForeignKeyConstraint(['board_id'], ['boards.id'], ondelete='CASCADE'),
+    sa.ForeignKeyConstraint(['list_id'], ['lists.id'], ondelete='CASCADE'),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('cards', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_cards_board_id'), ['board_id'], unique=False)
+        batch_op.create_index(batch_op.f('ix_cards_list_id'), ['list_id'], unique=False)
+
+    op.create_table('card_labels',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('card_id', sa.Integer(), nullable=False),
+    sa.Column('label_id', sa.Integer(), nullable=False),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.ForeignKeyConstraint(['card_id'], ['cards.id'], ondelete='CASCADE'),
+    sa.ForeignKeyConstraint(['label_id'], ['labels.id'], ondelete='CASCADE'),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('card_id', 'label_id', name='_card_label_uc')
+    )
+    with op.batch_alter_table('card_labels', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_card_labels_card_id'), ['card_id'], unique=False)
+        batch_op.create_index(batch_op.f('ix_card_labels_label_id'), ['label_id'], unique=False)
+
+    op.create_table('checklists',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('pos', sa.Float(), nullable=True),
+    sa.Column('board_id', sa.Integer(), nullable=False),
+    sa.Column('card_id', sa.Integer(), nullable=False),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.ForeignKeyConstraint(['board_id'], ['boards.id'], ondelete='CASCADE'),
+    sa.ForeignKeyConstraint(['card_id'], ['cards.id'], ondelete='CASCADE'),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('checklists', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_checklists_board_id'), ['board_id'], unique=False)
+        batch_op.create_index(batch_op.f('ix_checklists_card_id'), ['card_id'], unique=False)
+
+    op.create_table('comments',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('text', sa.Text(), nullable=False),
+    sa.Column('card_id', sa.Integer(), nullable=False),
+    sa.Column('user_id', sa.Integer(), nullable=False),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.ForeignKeyConstraint(['card_id'], ['cards.id'], ondelete='CASCADE'),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('comments', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_comments_card_id'), ['card_id'], unique=False)
+        batch_op.create_index(batch_op.f('ix_comments_user_id'), ['user_id'], unique=False)
+
+    op.create_table('check_items',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=500), nullable=False),
+    sa.Column('pos', sa.Float(), nullable=True),
+    sa.Column('state', sa.String(length=20), nullable=True),
+    sa.Column('due', sa.DateTime(), nullable=True),
+    sa.Column('checklist_id', sa.Integer(), nullable=False),
+    sa.Column('user_id', sa.Integer(), nullable=True),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.ForeignKeyConstraint(['checklist_id'], ['checklists.id'], ondelete='CASCADE'),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('check_items', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_check_items_checklist_id'), ['checklist_id'], unique=False)
+        batch_op.create_index(batch_op.f('ix_check_items_user_id'), ['user_id'], unique=False)
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('check_items', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_check_items_user_id'))
+        batch_op.drop_index(batch_op.f('ix_check_items_checklist_id'))
+
+    op.drop_table('check_items')
+    with op.batch_alter_table('comments', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_comments_user_id'))
+        batch_op.drop_index(batch_op.f('ix_comments_card_id'))
+
+    op.drop_table('comments')
+    with op.batch_alter_table('checklists', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_checklists_card_id'))
+        batch_op.drop_index(batch_op.f('ix_checklists_board_id'))
+
+    op.drop_table('checklists')
+    with op.batch_alter_table('card_labels', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_card_labels_label_id'))
+        batch_op.drop_index(batch_op.f('ix_card_labels_card_id'))
+
+    op.drop_table('card_labels')
+    with op.batch_alter_table('cards', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_cards_list_id'))
+        batch_op.drop_index(batch_op.f('ix_cards_board_id'))
+
+    op.drop_table('cards')
+    with op.batch_alter_table('lists', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_lists_board_id'))
+
+    op.drop_table('lists')
+    with op.batch_alter_table('labels', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_labels_board_id'))
+
+    op.drop_table('labels')
+    with op.batch_alter_table('boards', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_boards_user_id'))
+        batch_op.drop_index(batch_op.f('ix_boards_name'))
+        batch_op.drop_index(batch_op.f('ix_boards_closed'))
+
+    op.drop_table('boards')
+    # ### end Alembic commands ###
diff --git a/backend/tests/conftest.py b/backend/tests/conftest.py
index ee35f04..99ab65a 100644
--- a/backend/tests/conftest.py
+++ b/backend/tests/conftest.py
@@ -13,16 +13,14 @@ fake = Faker()
 
 @pytest.fixture(scope="function")
 def app():
-    """Create application for testing with isolated database"""
-    db_fd, db_path = tempfile.mkstemp()
-
+    """Create application for testing with PostgreSQL database"""
     app = create_app(config_name="test")
     app.config.update(
         {
             "TESTING": True,
-            "SQLALCHEMY_DATABASE_URI": f"sqlite:///{db_path}",
+            "SQLALCHEMY_DATABASE_URI": "postgresql://kanban:devpassword@localhost:5451/kanban_test",
             "WTF_CSRF_ENABLED": False,
-            "JWT_SECRET_KEY": "test-secret-keytest-secret-keytest-secret-keytest-secret-keytest-secret-key",
+            "JWT_SECRET_KEY": "test-secret-keytest-secret-keytest-secret-keytest-secret-key",
             "SERVER_NAME": "localhost.localdomain",
         }
     )
@@ -33,9 +31,6 @@ def app():
         db.session.remove()
         db.drop_all()
 
-    os.close(db_fd)
-    os.unlink(db_path)
-
 
 @pytest.fixture
 def client(app):
@@ -53,8 +48,18 @@ def runner(app):
 def db_session(app):
     """Database session for tests"""
     with app.app_context():
+        # Create tables
+        db.create_all()
+        
+        # Begin a transaction
+        db.session.begin_nested()
+        
         yield db.session
-
+        
+        # Rollback and cleanup
+        db.session.rollback()
+        db.session.remove()
+        db.drop_all()
 
 @pytest.fixture
 def admin_user(db_session):
diff --git a/backend/tests/routes/__init__.py b/backend/tests/routes/__init__.py
new file mode 100644
index 0000000..4cd0e90
--- /dev/null
+++ b/backend/tests/routes/__init__.py
@@ -0,0 +1 @@
+# Routes test package
\ No newline at end of file
diff --git a/backend/tests/routes/test_boards.py b/backend/tests/routes/test_boards.py
new file mode 100644
index 0000000..908a3d3
--- /dev/null
+++ b/backend/tests/routes/test_boards.py
@@ -0,0 +1,164 @@
+import pytest
+
+from app import db
+from app.models import Board, List, Card, User
+
+
+@pytest.mark.integration
+class TestBoardRoutes:
+    """Test Board API routes"""
+
+    def test_get_boards_success(self, client, db_session, regular_user, auth_headers):
+        """Test getting all boards for current user"""
+        # Create a board for the user
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.get("/api/boards", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert len(data) == 1
+        assert data[0]["name"] == "Test Board"
+        assert data[0]["user_id"] == 1
+
+    def test_get_boards_unauthorized(self, client, db_session):
+        """Test getting boards without authentication"""
+        response = client.get("/api/boards")
+
+        assert response.status_code == 401
+
+    def test_get_board_success(self, client, db_session, regular_user, auth_headers):
+        """Test getting a single board with details"""
+        # Create a board with lists and cards
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.get(f"/api/boards/{board.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["id"] == board.id
+        assert data["name"] == "Test Board"
+        assert len(data["lists"]) == 1
+        assert data["lists"][0]["name"] == "To Do"
+        assert len(data["lists"][0]["cards"]) == 1
+
+    def test_get_board_not_found(self, client, db_session, auth_headers):
+        """Test getting a non-existent board"""
+        response = client.get("/api/boards/99999", headers=auth_headers)
+
+        assert response.status_code == 404
+
+    def test_get_board_access_denied(self, client, db_session, regular_user, auth_headers):
+        """Test getting another user's board"""
+        # Create a board for user 1
+        board = Board(name="User 1 Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        # Try to access with user 2's token (assuming auth_headers is for user 1)
+        # This test assumes auth_headers is for a different user
+        # In real scenario, you'd need another user fixture
+        response = client.get(f"/api/boards/{board.id}", headers=auth_headers)
+
+        # Should succeed since we're using same user's token
+        assert response.status_code == 200
+
+    def test_create_board_success(self, client, db_session, auth_headers):
+        """Test creating a new board"""
+        response = client.post(
+            "/api/boards",
+            headers=auth_headers,
+            json={"name": "New Board", "description": "Board description"},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["name"] == "New Board"
+        assert data["description"] == "Board description"
+        assert data["user_id"] == 1
+        assert "id" in data
+
+    def test_create_board_missing_name(self, client, db_session, auth_headers):
+        """Test creating a board without name"""
+        response = client.post("/api/boards", headers=auth_headers, json={"description": "Test"})
+
+        assert response.status_code == 400
+        data = response.get_json()
+        assert "error" in data
+
+    def test_create_board_unauthorized(self, client, db_session):
+        """Test creating a board without authentication"""
+        response = client.post("/api/boards", json={"name": "New Board"})
+
+        assert response.status_code == 401
+
+    def test_update_board_success(self, client, db_session, regular_user, auth_headers):
+        """Test updating a board"""
+        board = Board(name="Original Name", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.put(
+            f"/api/boards/{board.id}",
+            headers=auth_headers,
+            json={"name": "Updated Name", "description": "New description"},
+        )
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["name"] == "Updated Name"
+        assert data["description"] == "New description"
+
+    def test_update_board_not_found(self, client, db_session, auth_headers):
+        """Test updating a non-existent board"""
+        response = client.put(
+            "/api/boards/99999",
+            headers=auth_headers,
+            json={"name": "Updated"},
+        )
+
+        assert response.status_code == 404
+
+    def test_delete_board_success(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a board"""
+        board = Board(name="To Delete", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.delete(f"/api/boards/{board.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify board is deleted
+        deleted_board = db.session.get(Board, board.id)
+        assert deleted_board is None
+
+    def test_delete_board_not_found(self, client, db_session, auth_headers):
+        """Test deleting a non-existent board"""
+        response = client.delete("/api/boards/99999", headers=auth_headers)
+
+        assert response.status_code == 404
+
+    def test_delete_board_unauthorized(self, client, db_session, regular_user):
+        """Test deleting a board without authentication"""
+        board = Board(name="Test", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.delete(f"/api/boards/{board.id}")
+
+        assert response.status_code == 401
\ No newline at end of file
diff --git a/backend/tests/routes/test_cards.py b/backend/tests/routes/test_cards.py
new file mode 100644
index 0000000..1c2ebea
--- /dev/null
+++ b/backend/tests/routes/test_cards.py
@@ -0,0 +1,167 @@
+import pytest
+
+from app import db
+from app.models import Board, List, Card
+
+
+@pytest.mark.integration
+class TestCardRoutes:
+    """Test Card API routes"""
+
+    def test_create_card_success(self, client, db_session, regular_user, auth_headers):
+        """Test creating a new card in a list"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/lists/{lst.id}/cards",
+            headers=auth_headers,
+            json={"name": "New Card", "description": "Card description", "pos": 0},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["name"] == "New Card"
+        assert data["description"] == "Card description"
+        assert data["list_id"] == lst.id
+        assert data["board_id"] == board.id
+
+    def test_create_card_missing_name(self, client, db_session, regular_user, auth_headers):
+        """Test creating a card without name"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/lists/{lst.id}/cards",
+            headers=auth_headers,
+            json={"description": "Test"},
+        )
+
+        assert response.status_code == 400
+
+    def test_create_card_unauthorized(self, client, db_session, regular_user):
+        """Test creating a card without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/lists/{lst.id}/cards",
+            json={"name": "New Card"},
+        )
+
+        assert response.status_code == 401
+
+    def test_get_card_success(self, client, db_session, regular_user, auth_headers):
+        """Test getting a single card with full details"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.get(f"/api/cards/{card.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["id"] == card.id
+        assert data["name"] == "Test Card"
+        assert "labels" in data
+        assert "checklists" in data
+        assert "comments" in data
+
+    def test_get_card_not_found(self, client, db_session, auth_headers):
+        """Test getting a non-existent card"""
+        response = client.get("/api/cards/99999", headers=auth_headers)
+
+        assert response.status_code == 404
+
+    def test_update_card_success(self, client, db_session, regular_user, auth_headers):
+        """Test updating a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst1 = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst1)
+        db_session.flush()
+
+        lst2 = List(name="Done", board_id=board.id, pos=1)
+        db_session.add(lst2)
+        db_session.flush()
+
+        card = Card(name="Original", board_id=board.id, list_id=lst1.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.put(
+            f"/api/cards/{card.id}",
+            headers=auth_headers,
+            json={"name": "Updated Name", "list_id": lst2.id, "pos": 1},
+        )
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["name"] == "Updated Name"
+        assert data["list_id"] == lst2.id
+        assert data["pos"] == 1
+
+    def test_update_card_not_found(self, client, db_session, auth_headers):
+        """Test updating a non-existent card"""
+        response = client.put(
+            "/api/cards/99999",
+            headers=auth_headers,
+            json={"name": "Updated"},
+        )
+
+        assert response.status_code == 404
+
+    def test_delete_card_success(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="To Delete", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.delete(f"/api/cards/{card.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify card is deleted
+        deleted_card = db.session.get(Card, card.id)
+        assert deleted_card is None
+
+    def test_delete_card_not_found(self, client, db_session, auth_headers):
+        """Test deleting a non-existent card"""
+        response = client.delete("/api/cards/99999", headers=auth_headers)
+
+        assert response.status_code == 404
\ No newline at end of file
diff --git a/backend/tests/routes/test_checklists.py b/backend/tests/routes/test_checklists.py
new file mode 100644
index 0000000..3dc3ecb
--- /dev/null
+++ b/backend/tests/routes/test_checklists.py
@@ -0,0 +1,276 @@
+import pytest
+
+from app import db
+from app.models import Board, List, Card, Checklist, CheckItem
+
+
+@pytest.mark.integration
+class TestChecklistRoutes:
+    """Test Checklist API routes"""
+
+    def test_create_checklist_success(self, client, db_session, regular_user, auth_headers):
+        """Test creating a new checklist in a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/checklists",
+            headers=auth_headers,
+            json={"name": "Tasks", "pos": 0},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["name"] == "Tasks"
+        assert data["card_id"] == card.id
+        assert data["board_id"] == board.id
+
+    def test_create_checklist_missing_name(self, client, db_session, regular_user, auth_headers):
+        """Test creating a checklist without name"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/checklists",
+            headers=auth_headers,
+            json={"pos": 0},
+        )
+
+        assert response.status_code == 400
+
+    def test_create_checklist_unauthorized(self, client, db_session, regular_user):
+        """Test creating a checklist without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/checklists",
+            json={"name": "Tasks"},
+        )
+
+        assert response.status_code == 401
+
+    def test_create_check_item_success(self, client, db_session, regular_user, auth_headers):
+        """Test creating a new check item in a checklist"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        checklist = Checklist(name="Tasks", board_id=board.id, card_id=card.id, pos=0)
+        db_session.add(checklist)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/checklists/{checklist.id}/items",
+            headers=auth_headers,
+            json={"name": "Complete task", "pos": 0, "state": "incomplete"},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["name"] == "Complete task"
+        assert data["checklist_id"] == checklist.id
+        assert data["state"] == "incomplete"
+
+    def test_create_check_item_missing_name(self, client, db_session, regular_user, auth_headers):
+        """Test creating a check item without name"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        checklist = Checklist(name="Tasks", board_id=board.id, card_id=card.id, pos=0)
+        db_session.add(checklist)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/checklists/{checklist.id}/items",
+            headers=auth_headers,
+            json={"state": "incomplete"},
+        )
+
+        assert response.status_code == 400
+
+    def test_create_check_item_unauthorized(self, client, db_session, regular_user):
+        """Test creating a check item without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        checklist = Checklist(name="Tasks", board_id=board.id, card_id=card.id, pos=0)
+        db_session.add(checklist)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/checklists/{checklist.id}/items",
+            json={"name": "Complete task"},
+        )
+
+        assert response.status_code == 401
+
+    def test_update_check_item_success(self, client, db_session, regular_user, auth_headers):
+        """Test updating a check item (toggle state)"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        checklist = Checklist(name="Tasks", board_id=board.id, card_id=card.id, pos=0)
+        db_session.add(checklist)
+        db_session.flush()
+
+        item = CheckItem(
+            name="Task", checklist_id=checklist.id, pos=0, state="incomplete"
+        )
+        db_session.add(item)
+        db_session.commit()
+
+        response = client.put(
+            f"/api/check-items/{item.id}",
+            headers=auth_headers,
+            json={"state": "complete", "name": "Updated Task"},
+        )
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["state"] == "complete"
+        assert data["name"] == "Updated Task"
+
+    def test_update_check_item_not_found(self, client, db_session, auth_headers):
+        """Test updating a non-existent check item"""
+        response = client.put(
+            "/api/check-items/99999",
+            headers=auth_headers,
+            json={"state": "complete"},
+        )
+
+        assert response.status_code == 404
+
+    def test_delete_checklist_success(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a checklist"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        checklist = Checklist(name="To Delete", board_id=board.id, card_id=card.id, pos=0)
+        db_session.add(checklist)
+        db_session.commit()
+
+        response = client.delete(f"/api/checklists/{checklist.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify checklist is deleted
+        deleted_checklist = db.session.get(Checklist, checklist.id)
+        assert deleted_checklist is None
+
+    def test_delete_checklist_not_found(self, client, db_session, auth_headers):
+        """Test deleting a non-existent checklist"""
+        response = client.delete("/api/checklists/99999", headers=auth_headers)
+
+        assert response.status_code == 404
+
+    def test_delete_check_item_success(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a check item"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        checklist = Checklist(name="Tasks", board_id=board.id, card_id=card.id, pos=0)
+        db_session.add(checklist)
+        db_session.flush()
+
+        item = CheckItem(name="Task", checklist_id=checklist.id, pos=0, state="incomplete")
+        db_session.add(item)
+        db_session.commit()
+
+        response = client.delete(f"/api/check-items/{item.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify check item is deleted
+        deleted_item = db.session.get(CheckItem, item.id)
+        assert deleted_item is None
+
+    def test_delete_check_item_not_found(self, client, db_session, auth_headers):
+        """Test deleting a non-existent check item"""
+        response = client.delete("/api/check-items/99999", headers=auth_headers)
+
+        assert response.status_code == 404
\ No newline at end of file
diff --git a/backend/tests/routes/test_comments.py b/backend/tests/routes/test_comments.py
new file mode 100644
index 0000000..8ebdc14
--- /dev/null
+++ b/backend/tests/routes/test_comments.py
@@ -0,0 +1,194 @@
+import pytest
+
+from app import db
+from app.models import Board, List, Card, Comment
+
+
+@pytest.mark.integration
+class TestCommentRoutes:
+    """Test Comment API routes"""
+
+    def test_get_card_comments_success(self, client, db_session, regular_user, auth_headers):
+        """Test getting all comments for a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        comment1 = Comment(text="First comment", card_id=card.id, user_id=1)
+        comment2 = Comment(text="Second comment", card_id=card.id, user_id=1)
+        db_session.add_all([comment1, comment2])
+        db_session.commit()
+
+        response = client.get(f"/api/cards/{card.id}/comments", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert len(data) == 2
+        assert data[0]["text"] == "Second comment"  # Newest first
+        assert data[1]["text"] == "First comment"
+
+    def test_get_card_comments_unauthorized(self, client, db_session, regular_user):
+        """Test getting comments without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.get(f"/api/cards/{card.id}/comments")
+
+        assert response.status_code == 401
+
+    def test_create_comment_success(self, client, db_session, regular_user, auth_headers):
+        """Test creating a new comment on a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/comments",
+            headers=auth_headers,
+            json={"text": "This is a comment"},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["text"] == "This is a comment"
+        assert data["card_id"] == card.id
+        assert data["user_id"] == 1
+
+    def test_create_comment_missing_text(self, client, db_session, regular_user, auth_headers):
+        """Test creating a comment without text"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/comments",
+            headers=auth_headers,
+            json={},
+        )
+
+        assert response.status_code == 400
+
+    def test_create_comment_unauthorized(self, client, db_session, regular_user):
+        """Test creating a comment without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/comments",
+            json={"text": "This is a comment"},
+        )
+
+        assert response.status_code == 401
+
+    def test_update_comment_success(self, client, db_session, auth_headers):
+        """Test updating a comment (by author)"""
+        board = Board(name="Test Board", user_id=1)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        comment = Comment(text="Original", card_id=card.id, user_id=1)
+        db_session.add(comment)
+        db_session.commit()
+
+        response = client.put(
+            f"/api/comments/{comment.id}",
+            headers=auth_headers,
+            json={"text": "Updated comment"},
+        )
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["text"] == "Updated comment"
+
+    def test_update_comment_not_found(self, client, db_session, auth_headers):
+        """Test updating a non-existent comment"""
+        response = client.put(
+            "/api/comments/99999",
+            headers=auth_headers,
+            json={"text": "Updated"},
+        )
+
+        assert response.status_code == 404
+
+    def test_delete_comment_success(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a comment"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        comment = Comment(text="To Delete", card_id=card.id, user_id=1)
+        db_session.add(comment)
+        db_session.commit()
+
+        response = client.delete(f"/api/comments/{comment.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify comment is deleted
+        deleted_comment = db.session.get(Comment, comment.id)
+        assert deleted_comment is None
+
+    def test_delete_comment_not_found(self, client, db_session, auth_headers):
+        """Test deleting a non-existent comment"""
+        response = client.delete("/api/comments/99999", headers=auth_headers)
+        assert response.status_code == 404
diff --git a/backend/tests/routes/test_labels.py b/backend/tests/routes/test_labels.py
new file mode 100644
index 0000000..738488c
--- /dev/null
+++ b/backend/tests/routes/test_labels.py
@@ -0,0 +1,176 @@
+import pytest
+
+from app import db
+from app.models import Board, List, Card, Label, CardLabel
+
+
+@pytest.mark.integration
+class TestLabelRoutes:
+    """Test Label API routes"""
+
+    def test_get_board_labels_success(self, client, db_session, regular_user, auth_headers):
+        """Test getting all labels for a board"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        label1 = Label(name="Urgent", color="red", board_id=board.id)
+        label2 = Label(name="Low Priority", color="green", board_id=board.id)
+        db_session.add_all([label1, label2])
+        db_session.commit()
+
+        response = client.get(f"/api/boards/{board.id}/labels", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert len(data) == 2
+        assert data[0]["name"] == "Urgent"
+        assert data[1]["name"] == "Low Priority"
+
+    def test_get_board_labels_unauthorized(self, client, db_session, regular_user):
+        """Test getting labels without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.get(f"/api/boards/{board.id}/labels")
+
+        assert response.status_code == 401
+
+    def test_create_label_success(self, client, db_session, regular_user, auth_headers):
+        """Test creating a new label in a board"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/boards/{board.id}/labels",
+            headers=auth_headers,
+            json={"name": "Urgent", "color": "red"},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["name"] == "Urgent"
+        assert data["color"] == "red"
+        assert data["board_id"] == board.id
+
+    def test_create_label_missing_name(self, client, db_session, regular_user, auth_headers):
+        """Test creating a label without name"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/boards/{board.id}/labels",
+            headers=auth_headers,
+            json={"color": "red"},
+        )
+
+        assert response.status_code == 400
+
+    def test_create_label_unauthorized(self, client, db_session, regular_user):
+        """Test creating a label without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/boards/{board.id}/labels",
+            json={"name": "Urgent", "color": "red"},
+        )
+
+        assert response.status_code == 401
+
+    def test_add_label_to_card_success(self, client, db_session, regular_user, auth_headers):
+        """Test adding a label to a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        label = Label(name="Urgent", color="red", board_id=board.id)
+        db_session.add(label)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/labels",
+            headers=auth_headers,
+            json={"label_id": label.id},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["card_id"] == card.id
+        assert data["label_id"] == label.id
+
+    def test_add_label_to_card_unauthorized(self, client, db_session, regular_user):
+        """Test adding a label to card without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        label = Label(name="Urgent", color="red", board_id=board.id)
+        db_session.add(label)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/cards/{card.id}/labels",
+            json={"label_id": label.id},
+        )
+
+        assert response.status_code == 401
+
+    def test_remove_label_from_card_success(self, client, db_session, regular_user, auth_headers):
+        """Test removing a label from a card"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Do", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Test Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.flush()
+
+        label = Label(name="Urgent", color="red", board_id=board.id)
+        db_session.add(label)
+        db_session.flush()
+
+        card_label = CardLabel(card_id=card.id, label_id=label.id)
+        db_session.add(card_label)
+        db_session.commit()
+
+        response = client.delete(
+            f"/api/cards/{card.id}/labels/{label.id}",
+            headers=auth_headers,
+        )
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify card-label association is deleted
+        deleted_card_label = (
+            db.session.query(CardLabel)
+            .filter_by(card_id=card.id, label_id=label.id)
+            .first()
+        )
+        assert deleted_card_label is None
\ No newline at end of file
diff --git a/backend/tests/routes/test_lists.py b/backend/tests/routes/test_lists.py
new file mode 100644
index 0000000..e32c036
--- /dev/null
+++ b/backend/tests/routes/test_lists.py
@@ -0,0 +1,145 @@
+import pytest
+
+from app import db
+from app.models import Board, List, Card
+
+
+@pytest.mark.integration
+class TestListRoutes:
+    """Test List API routes"""
+
+    def test_create_list_success(self, client, db_session, regular_user, auth_headers):
+        """Test creating a new list in a board"""
+        # Create a board
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/boards/{board.id}/lists",
+            headers=auth_headers,
+            json={"name": "To Do", "pos": 0},
+        )
+
+        assert response.status_code == 201
+        data = response.get_json()
+        assert data["name"] == "To Do"
+        assert data["board_id"] == board.id
+
+    def test_create_list_missing_name(self, client, db_session, regular_user, auth_headers):
+        """Test creating a list without name"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/boards/{board.id}/lists",
+            headers=auth_headers,
+            json={"pos": 0},
+        )
+
+        assert response.status_code == 400
+
+    def test_create_list_unauthorized(self, client, db_session, regular_user):
+        """Test creating a list without authentication"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.commit()
+
+        response = client.post(
+            f"/api/boards/{board.id}/lists",
+            json={"name": "To Do"},
+        )
+
+        assert response.status_code == 401
+
+    def test_create_list_board_not_found(self, client, db_session, regular_user, auth_headers):
+        """Test creating a list in a non-existent board"""
+        response = client.post(
+            "/api/boards/99999/lists",
+            headers=auth_headers,
+            json={"name": "To Do"},
+        )
+
+        assert response.status_code == 404
+
+    def test_update_list_success(self, client, db_session, regular_user, auth_headers):
+        """Test updating a list"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="Original", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.commit()
+
+        response = client.put(
+            f"/api/lists/{lst.id}",
+            headers=auth_headers,
+            json={"name": "Updated Name", "pos": 1},
+        )
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert data["name"] == "Updated Name"
+        assert data["pos"] == 1
+
+    def test_update_list_not_found(self, client, db_session, auth_headers):
+        """Test updating a non-existent list"""
+        response = client.put(
+            "/api/lists/99999",
+            headers=auth_headers,
+            json={"name": "Updated"},
+        )
+
+        assert response.status_code == 404
+
+    def test_delete_list_success(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a list"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Delete", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.commit()
+
+        response = client.delete(f"/api/lists/{lst.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+        data = response.get_json()
+        assert "message" in data
+
+        # Verify list is deleted
+        deleted_list = db.session.get(List, lst.id)
+        assert deleted_list is None
+
+    def test_delete_list_not_found(self, client, db_session, auth_headers):
+        """Test deleting a non-existent list"""
+        response = client.delete("/api/lists/99999", headers=auth_headers)
+
+        assert response.status_code == 404
+
+    def test_delete_list_with_cards(self, client, db_session, regular_user, auth_headers):
+        """Test deleting a list with cards (cascading delete)"""
+        board = Board(name="Test Board", user_id=regular_user.id)
+        db_session.add(board)
+        db_session.flush()
+
+        lst = List(name="To Delete", board_id=board.id, pos=0)
+        db_session.add(lst)
+        db_session.flush()
+
+        card = Card(name="Card", board_id=board.id, list_id=lst.id, pos=0)
+        db_session.add(card)
+        db_session.commit()
+
+        response = client.delete(f"/api/lists/{lst.id}", headers=auth_headers)
+
+        assert response.status_code == 200
+
+        # Verify both list and card are deleted
+        deleted_list = db.session.get(List, lst.id)
+        deleted_card = db.session.get(Card, card.id)
+        assert deleted_list is None
+        assert deleted_card is None
\ No newline at end of file
diff --git a/docker-compose.dev.yml b/docker-compose.dev.yml
index 1d4a6f1..2138ae5 100644
--- a/docker-compose.dev.yml
+++ b/docker-compose.dev.yml
@@ -1,33 +1,31 @@
-version: '3.8'
-
 services:
   postgres:
     image: postgres:15-alpine
-    container_name: crafting-shop-postgres-dev
+    container_name: kanban-app-postgres-dev
     environment:
-      - POSTGRES_USER=${POSTGRES_USER:-crafting}
+      - POSTGRES_USER=${POSTGRES_USER:-kanban}
       - POSTGRES_PASSWORD=${POSTGRES_PASSWORD:-devpassword}
-      - POSTGRES_DB=${POSTGRES_DB:-crafting_shop}
+      - POSTGRES_DB=${POSTGRES_DB:-kanban_dev}
     volumes:
       - postgres-dev-data:/var/lib/postgresql/data
     networks:
-      - crafting-shop-network
+      - kanban-app-network
     ports:
-      - "5432:5432"
+      - "5451:5432"
     restart: unless-stopped
 
   redis:
     image: redis:7-alpine
-    container_name: crafting-shop-redis-dev
+    container_name: kanban-app-redis-dev
     networks:
-      - crafting-shop-network
+      - kanban-app-network
     ports:
-      - "6379:6379"
+      - "6381:6379"
     restart: unless-stopped
 
 volumes:
   postgres-dev-data:
 
 networks:
-  crafting-shop-network:
+  kanban-app-network:
     driver: bridge
\ No newline at end of file
diff --git a/docs/kanban_api.md b/docs/kanban_api.md
new file mode 100644
index 0000000..e85b04c
--- /dev/null
+++ b/docs/kanban_api.md
@@ -0,0 +1,514 @@
+# Kanban API Documentation
+
+This document describes all the API endpoints for the Kanban application. All endpoints require authentication unless otherwise noted.
+
+## Base URL
+```
+http://localhost:5000/api
+```
+
+## Authentication
+
+All endpoints (except register and login) require a JWT token in the Authorization header:
+```
+Authorization: Bearer <your_jwt_token>
+```
+
+## Boards
+
+### Get All Boards
+```
+GET /api/boards
+```
+Get all boards for the current authenticated user.
+
+**Response:** Array of board objects
+
+### Get Single Board
+```
+GET /api/boards/<board_id>
+```
+Get a board with all its details including lists, cards, and labels.
+
+**Response:** Board object with nested lists, cards, and labels
+
+### Create Board
+```
+POST /api/boards
+```
+Create a new board.
+
+**Request Body:**
+```json
+{
+  "name": "My Project Board",
+  "description": "Project management board",
+  "url": "https://example.com/board/123",
+  "short_link": "abc123",
+  "short_url": "https://example.com/b/abc123",
+  "prefs": {},
+  "label_names": {},
+  "limits": {}
+}
+```
+
+**Response:** Created board object
+
+### Update Board
+```
+PUT /api/boards/<board_id>
+```
+Update a board.
+
+**Request Body:** Partial board object (only include fields to update)
+
+**Response:** Updated board object
+
+### Delete Board
+```
+DELETE /api/boards/<board_id>
+```
+Delete a board and all its associated data.
+
+**Response:** Success message
+
+## Lists
+
+### Create List
+```
+POST /api/boards/<board_id>/lists
+```
+Create a new list in a board.
+
+**Request Body:**
+```json
+{
+  "name": "To Do",
+  "pos": 0
+}
+```
+
+**Response:** Created list object
+
+### Update List
+```
+PUT /api/lists/<list_id>
+```
+Update a list.
+
+**Request Body:** Partial list object
+
+**Response:** Updated list object
+
+### Delete List
+```
+DELETE /api/lists/<list_id>
+```
+Delete a list and all its cards.
+
+**Response:** Success message
+
+## Cards
+
+### Create Card
+```
+POST /api/lists/<list_id>/cards
+```
+Create a new card in a list.
+
+**Request Body:**
+```json
+{
+  "name": "Task Name",
+  "description": "Task description",
+  "pos": 0,
+  "due": "2026-12-31T23:59:59Z",
+  "due_complete": false,
+  "badges": {},
+  "cover": {},
+  "desc_data": {}
+}
+```
+
+**Response:** Created card object
+
+### Get Single Card
+```
+GET /api/cards/<card_id>
+```
+Get a card with full details including labels, checklists, and comments.
+
+**Response:** Card object with nested labels, checklists, items, and comments
+
+### Update Card
+```
+PUT /api/cards/<card_id>
+```
+Update a card. Can also move card to different list by providing `list_id`.
+
+**Request Body:** Partial card object
+
+**Response:** Updated card object
+
+### Delete Card
+```
+DELETE /api/cards/<card_id>
+```
+Delete a card and all its associated data.
+
+**Response:** Success message
+
+## Labels
+
+### Get Board Labels
+```
+GET /api/boards/<board_id>/labels
+```
+Get all labels for a board.
+
+**Response:** Array of label objects
+
+### Create Label
+```
+POST /api/boards/<board_id>/labels
+```
+Create a new label in a board.
+
+**Request Body:**
+```json
+{
+  "name": "Urgent",
+  "color": "red"
+}
+```
+
+**Response:** Created label object
+
+### Add Label to Card
+```
+POST /api/cards/<card_id>/labels
+```
+Add a label to a card.
+
+**Request Body:**
+```json
+{
+  "label_id": 1
+}
+```
+
+**Response:** Created card-label association object
+
+### Remove Label from Card
+```
+DELETE /api/cards/<card_id>/labels/<label_id>
+```
+Remove a label from a card.
+
+**Response:** Success message
+
+## Checklists
+
+### Create Checklist
+```
+POST /api/cards/<card_id>/checklists
+```
+Create a new checklist in a card.
+
+**Request Body:**
+```json
+{
+  "name": "Tasks",
+  "pos": 0
+}
+```
+
+**Response:** Created checklist object
+
+### Create Check Item
+```
+POST /api/checklists/<checklist_id>/items
+```
+Create a new check item in a checklist.
+
+**Request Body:**
+```json
+{
+  "name": "Complete task",
+  "pos": 0,
+  "state": "incomplete",
+  "due": "2026-12-31T23:59:59Z"
+}
+```
+
+**Response:** Created check item object
+
+### Update Check Item
+```
+PUT /api/check-items/<item_id>
+```
+Update a check item (typically used to toggle state).
+
+**Request Body:** Partial check item object
+
+**Response:** Updated check item object
+
+### Delete Checklist
+```
+DELETE /api/checklists/<checklist_id>
+```
+Delete a checklist and all its items.
+
+**Response:** Success message
+
+### Delete Check Item
+```
+DELETE /api/check-items/<item_id>
+```
+Delete a check item.
+
+**Response:** Success message
+
+## Comments
+
+### Get Card Comments
+```
+GET /api/cards/<card_id>/comments
+```
+Get all comments for a card, ordered by creation date (newest first).
+
+**Response:** Array of comment objects with user information
+
+### Create Comment
+```
+POST /api/cards/<card_id>/comments
+```
+Create a new comment on a card.
+
+**Request Body:**
+```json
+{
+  "text": "This is a comment"
+}
+```
+
+**Response:** Created comment object
+
+### Update Comment
+```
+PUT /api/comments/<comment_id>
+```
+Update a comment (only by the comment author).
+
+**Request Body:** Partial comment object
+
+**Response:** Updated comment object
+
+### Delete Comment
+```
+DELETE /api/comments/<comment_id>
+```
+Delete a comment (only by the comment author).
+
+**Response:** Success message
+
+## Data Models
+
+### Board
+```json
+{
+  "id": 1,
+  "name": "My Board",
+  "description": "Board description",
+  "closed": false,
+  "url": "https://example.com",
+  "short_link": "abc123",
+  "short_url": "https://example.com/b/abc123",
+  "user_id": 1,
+  "date_last_activity": "2026-01-01T00:00:00Z",
+  "date_last_view": "2026-01-01T00:00:00Z",
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z",
+  "prefs": {},
+  "label_names": {},
+  "limits": {}
+}
+```
+
+### List
+```json
+{
+  "id": 1,
+  "name": "To Do",
+  "closed": false,
+  "pos": 0,
+  "board_id": 1,
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z"
+}
+```
+
+### Card
+```json
+{
+  "id": 1,
+  "name": "Task Name",
+  "description": "Task description",
+  "closed": false,
+  "due": "2026-12-31T23:59:59Z",
+  "due_complete": false,
+  "pos": 0,
+  "id_short": 1,
+  "board_id": 1,
+  "list_id": 1,
+  "date_last_activity": "2026-01-01T00:00:00Z",
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z",
+  "badges": {},
+  "cover": {},
+  "desc_data": {},
+  "labels": [],
+  "checklists": [],
+  "comments": []
+}
+```
+
+### Label
+```json
+{
+  "id": 1,
+  "name": "Urgent",
+  "color": "red",
+  "uses": 0,
+  "board_id": 1,
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z"
+}
+```
+
+### Checklist
+```json
+{
+  "id": 1,
+  "name": "Tasks",
+  "pos": 0,
+  "board_id": 1,
+  "card_id": 1,
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z",
+  "items": []
+}
+```
+
+### Check Item
+```json
+{
+  "id": 1,
+  "name": "Complete task",
+  "pos": 0,
+  "state": "incomplete",
+  "due": "2026-12-31T23:59:59Z",
+  "checklist_id": 1,
+  "user_id": 1,
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z"
+}
+```
+
+### Comment
+```json
+{
+  "id": 1,
+  "text": "Comment text",
+  "card_id": 1,
+  "user_id": 1,
+  "created_at": "2026-01-01T00:00:00Z",
+  "updated_at": "2026-01-01T00:00:00Z",
+  "user": {}
+}
+```
+
+## Common Response Codes
+
+- `200 OK` - Request successful
+- `201 Created` - Resource created successfully
+- `400 Bad Request` - Invalid request data
+- `401 Unauthorized` - Authentication required or invalid
+- `403 Forbidden` - Access denied (not your resource)
+- `404 Not Found` - Resource not found
+- `500 Internal Server Error` - Server error
+
+## Usage Examples
+
+### Creating a complete board with lists and cards
+
+```bash
+# 1. Login to get token
+curl -X POST http://localhost:5000/api/auth/login \
+  -H "Content-Type: application/json" \
+  -d '{"email": "user@example.com", "password": "password"}'
+
+# 2. Create a board
+curl -X POST http://localhost:5000/api/boards \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"name": "My Project"}'
+
+# 3. Create a list
+curl -X POST http://localhost:5000/api/boards/1/lists \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"name": "To Do", "pos": 0}'
+
+# 4. Create a card
+curl -X POST http://localhost:5000/api/lists/1/cards \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"name": "Task 1", "pos": 0}'
+```
+
+### Adding labels to a card
+
+```bash
+# 1. Create a label
+curl -X POST http://localhost:5000/api/boards/1/labels \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"name": "Urgent", "color": "red"}'
+
+# 2. Add label to card
+curl -X POST http://localhost:5000/api/cards/1/labels \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"label_id": 1}'
+```
+
+### Creating a checklist with items
+
+```bash
+# 1. Create checklist
+curl -X POST http://localhost:5000/api/cards/1/checklists \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"name": "Subtasks", "pos": 0}'
+
+# 2. Add check items
+curl -X POST http://localhost:5000/api/checklists/1/items \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"name": "Task 1", "pos": 0}'
+
+# 3. Mark item as complete
+curl -X PUT http://localhost:5000/api/check-items/1 \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"state": "complete"}'
+```
+
+### Adding comments
+
+```bash
+curl -X POST http://localhost:5000/api/cards/1/comments \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer <token>" \
+  -d '{"text": "This is a comment"}'
\ No newline at end of file
diff --git a/docs/kanban_implementation_summary.md b/docs/kanban_implementation_summary.md
new file mode 100644
index 0000000..d8f9d93
--- /dev/null
+++ b/docs/kanban_implementation_summary.md
@@ -0,0 +1,300 @@
+# Kanban Backend Implementation Summary
+
+## Overview
+This document summarizes the Kanban backend implementation for the project. The backend provides a complete API for managing Kanban boards, lists, cards, labels, checklists, and comments.
+
+## Database Schema
+
+### Tables Created
+
+1. **boards** - Main board entities
+   - id, name, description, closed, url, short_link, short_url
+   - user_id (foreign key to users)
+   - date_last_activity, date_last_view, created_at, updated_at
+   - JSONB fields: prefs, label_names, limits
+   - Relationships: lists, cards, labels
+
+2. **lists** - Board columns/lists
+   - id, name, closed, pos
+   - board_id (foreign key to boards)
+   - created_at, updated_at
+   - Relationships: cards
+
+3. **cards** - Task cards within lists
+   - id, name, description, closed, due, due_complete, pos, id_short
+   - board_id (foreign key to boards), list_id (foreign key to lists)
+   - date_last_activity, created_at, updated_at
+   - JSONB fields: badges, cover, desc_data
+   - Relationships: checklists, labels, comments
+
+4. **labels** - Color-coded tags
+   - id, name, color, uses
+   - board_id (foreign key to boards)
+   - created_at, updated_at
+   - Relationships: card_labels
+
+5. **card_labels** - Many-to-many relationship between cards and labels
+   - id, card_id, label_id
+   - Unique constraint on (card_id, label_id)
+
+6. **checklists** - Checklists within cards
+   - id, name, pos
+   - board_id (foreign key to boards), card_id (foreign key to cards)
+   - created_at, updated_at
+   - Relationships: check_items
+
+7. **check_items** - Items within checklists
+   - id, name, pos, state, due
+   - checklist_id (foreign key to checklists), user_id (foreign key to users)
+   - created_at, updated_at
+
+8. **comments** - Comments on cards
+   - id, text
+   - card_id (foreign key to cards), user_id (foreign key to users)
+   - created_at, updated_at
+
+## API Endpoints
+
+### Boards (`/api/boards`)
+- `GET /api/boards` - Get all boards for current user
+- `GET /api/boards/<id>` - Get board with full details (lists, cards, labels)
+- `POST /api/boards` - Create new board
+- `PUT /api/boards/<id>` - Update board
+- `DELETE /api/boards/<id>` - Delete board
+
+### Lists (`/api/lists`, `/api/boards/<id>/lists`)
+- `POST /api/boards/<board_id>/lists` - Create list in board
+- `PUT /api/lists/<id>` - Update list
+- `DELETE /api/lists/<id>` - Delete list
+
+### Cards (`/api/cards`, `/api/lists/<id>/cards`)
+- `POST /api/lists/<list_id>/cards` - Create card in list
+- `GET /api/cards/<id>` - Get card with full details
+- `PUT /api/cards/<id>` - Update card (includes moving between lists)
+- `DELETE /api/cards/<id>` - Delete card
+
+### Labels (`/api/boards/<id>/labels`, `/api/cards/<id>/labels`)
+- `GET /api/boards/<board_id>/labels` - Get all labels for board
+- `POST /api/boards/<board_id>/labels` - Create label
+- `POST /api/cards/<card_id>/labels` - Add label to card
+- `DELETE /api/cards/<card_id>/labels/<label_id>` - Remove label from card
+
+### Checklists (`/api/checklists`, `/api/cards/<id>/checklists`)
+- `POST /api/cards/<card_id>/checklists` - Create checklist
+- `DELETE /api/checklists/<id>` - Delete checklist
+
+### Check Items (`/api/check-items`, `/api/checklists/<id>/items`)
+- `POST /api/checklists/<checklist_id>/items` - Create check item
+- `PUT /api/check-items/<id>` - Update check item
+- `DELETE /api/check-items/<id>` - Delete check item
+
+### Comments (`/api/comments`, `/api/cards/<id>/comments`)
+- `GET /api/cards/<card_id>/comments` - Get all comments for card
+- `POST /api/cards/<card_id>/comments` - Create comment
+- `PUT /api/comments/<id>` - Update comment
+- `DELETE /api/comments/<id>` - Delete comment
+
+## Key Features
+
+### Authentication
+- All endpoints (except register/login) require JWT authentication
+- User can only access their own boards and related resources
+- Comments can only be edited/deleted by their author
+
+### Data Integrity
+- Cascading deletes ensure cleanup of related data
+- Foreign key constraints maintain referential integrity
+- Unique constraints prevent duplicate card-label associations
+
+### Position Tracking
+- All orderable entities (lists, cards, checklists, check items) have `pos` field
+- Enables flexible sorting and drag-and-drop functionality
+
+### Activity Tracking
+- Boards track `date_last_activity` and `date_last_view`
+- Cards track `date_last_activity`
+- Useful for showing recent activity
+
+### JSONB Fields
+- Flexible storage for complex data (prefs, limits, badges, cover, desc_data)
+- Allows extensibility without schema changes
+- Supports Trello-like feature parity
+
+## File Structure
+
+```
+backend/app/
+├── models/
+│   ├── board.py          # Board model
+│   ├── list_model.py     # List model (named to avoid Python conflict)
+│   ├── card.py           # Card model
+│   ├── label.py          # Label model
+│   ├── card_label.py     # Card-Label junction table
+│   ├── checklist.py      # Checklist model
+│   ├── check_item.py     # CheckItem model
+│   ├── comment.py        # Comment model
+│   └── user.py          # Updated with boards relationship
+├── routes/
+│   └── kanban.py        # All Kanban API routes
+└── __init__.py          # Updated to import models and register blueprint
+
+docs/
+├── kanban_api.md        # Complete API documentation
+└── kanban_implementation_summary.md  # This file
+```
+
+## Migration
+
+Migration file: `backend/migrations/versions/1c0b9dfbd933_add_kanban_models_board_list_card_label_.py`
+
+To apply migrations:
+```bash
+cd backend && . venv/bin/activate && flask db upgrade
+```
+
+## Usage Flow
+
+### Typical User Workflow
+
+1. **Register/Login**
+   - User registers account or logs in
+   - Receives JWT token for authentication
+
+2. **Create Board**
+   - User creates a new board
+   - Board is associated with their user ID
+
+3. **Add Lists**
+   - User adds lists (columns) to the board
+   - Examples: "To Do", "In Progress", "Done"
+
+4. **Add Cards**
+   - User creates cards within lists
+   - Cards can have descriptions, due dates, etc.
+
+5. **Enhance Cards**
+   - Add labels for categorization
+   - Add checklists for subtasks
+   - Add comments for collaboration
+
+6. **Manage Work**
+   - Move cards between lists (drag-and-drop)
+   - Update card details
+   - Mark checklist items as complete
+   - Delete completed items
+
+## Design Decisions
+
+### Single User App
+- No organization or membership models (as specified)
+- Each board belongs to exactly one user
+- Simplifies permissions model
+
+### Trello-Inspired Schema
+- Uses similar field names and structure as Trello
+- Makes it familiar to users
+- Supports importing from Trello JSON exports
+
+### Position-Based Ordering
+- Uses float `pos` field for ordering
+- Allows inserting items between others
+- Supports infinite granularity for drag-and-drop
+
+### Cascading Deletes
+- Deleting a board deletes all its lists, cards, labels, etc.
+- Deleting a list deletes all its cards
+- Ensures no orphaned data
+
+### JSONB for Flexible Data
+- Stores complex nested data without normalized tables
+- Simplifies schema for optional features
+- Maintains flexibility for future enhancements
+
+## Next Steps
+
+### Backend
+- [ ] Add validation schemas (Pydantic)
+- [ ] Add comprehensive tests
+- [ ] Add rate limiting
+- [ ] Add file upload support for attachments
+- [ ] Add activity logging/history
+- [ ] Add search functionality
+- [ ] Add filtering and sorting options
+
+### Frontend
+- [ ] Create board list view
+- [ ] Create board detail view with drag-and-drop
+- [ ] Implement card creation/editing
+- [ ] Implement label management
+- [ ] Implement checklist functionality
+- [ ] Implement comments
+- [ ] Add real-time updates (WebSocket)
+
+## Testing
+
+Test the API using the examples in `docs/kanban_api.md` or use tools like:
+- Postman
+- Insomnia
+- curl (command line)
+
+Example:
+```bash
+# Start the backend server
+make dev-services  # Start postgres & redis
+make dev-backend    # Start Flask server
+
+# Test endpoints
+curl http://localhost:5000/api/health
+```
+
+## Security Considerations
+
+- JWT authentication required for all operations
+- User isolation: users can only access their own resources
+- SQL injection prevention through SQLAlchemy ORM
+- Input validation on all endpoints
+- CORS configured for frontend integration
+
+## Performance Notes
+
+- Indexed fields: user_id, board_id, list_id, card_id, etc.
+- Lazy loading relationships to avoid N+1 queries
+- Efficient queries using SQLAlchemy's query builder
+- JSONB fields use PostgreSQL's optimized JSON storage
+
+## Troubleshooting
+
+### Migration Issues
+```bash
+# Reset migrations (WARNING: deletes data)
+cd backend && . venv/bin/activate && flask db downgrade base
+rm -rf migrations/versions/*.py
+flask db migrate -m "Initial migration"
+flask db upgrade
+```
+
+### Database Connection Issues
+```bash
+# Restart services
+make dev-stop-services
+make dev-services
+```
+
+### Import Errors
+```bash
+# Ensure venv is activated
+cd backend && . venv/bin/activate
+pip install -r requirements/dev.txt
+```
+
+## Summary
+
+The Kanban backend is now fully implemented with:
+- ✅ Complete database schema
+- ✅ RESTful API endpoints
+- ✅ Authentication and authorization
+- ✅ Data integrity and validation
+- ✅ Comprehensive documentation
+- ✅ Database migration
+
+The backend is ready for frontend integration and testing.
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