fix: remove hardcoded default secrets from API config

Remove dangerous default values for jwt_secret_key, service_key, and
fernet_key. Add startup validation that raises RuntimeError if these
secrets are not set via environment variables or contain placeholder
values.

Add test fixture to provide explicit test values for these secrets,
ensuring existing tests continue to pass.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

api/alembic/env.py

@@ -6,7 +6,7 @@ from logging.config import fileConfig
 from sqlalchemy import engine_from_config, pool
 
 from alembic import context
-from cartsnitch_api.models.base import Base  # noqa: F401 — imports all models for autogenerate
+from cartsnitch_api.models import Base  # noqa: F401 — imports all models for autogenerate
 
 config = context.config
 if config.config_file_name is not None:
@@ -53,6 +53,7 @@ def run_migrations_online() -> None:
         # checkfirst=True ensures this is a no-op on existing databases.
         try:
             Base.metadata.create_all(bind=connection, checkfirst=True)
+            connection.commit()
         except Exception as exc:
             import logging
             logging.getLogger("alembic.env").warning(

api/alembic/versions/008_create_domain_tables.py

@@ -0,0 +1,210 @@
+"""Create domain tables (stores, purchases, coupons, etc.).
+
+Revision ID: 008_create_domain_tables
+Revises: 007_bootstrap_users_table
+Create Date: 2026-04-04
+"""
+
+import sqlalchemy as sa
+from sqlalchemy import text
+
+from alembic import op
+
+revision = "008_create_domain_tables"
+down_revision = "007_bootstrap_users_table"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    inspector = sa.inspect(conn)
+
+    # 1. stores
+    if not inspector.has_table("stores"):
+        op.create_table(
+            "stores",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("name", sa.String(100), nullable=False),
+            sa.Column("slug", sa.String(20), nullable=False, unique=True),
+            sa.Column("logo_url", sa.String(500), nullable=True),
+            sa.Column("website_url", sa.String(500), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        )
+
+    # 2. store_locations
+    if not inspector.has_table("store_locations"):
+        op.create_table(
+            "store_locations",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("store_id", sa.Uuid(), sa.ForeignKey("stores.id"), nullable=False),
+            sa.Column("address", sa.String(300), nullable=False),
+            sa.Column("city", sa.String(100), nullable=False),
+            sa.Column("state", sa.String(2), nullable=False),
+            sa.Column("zip", sa.String(10), nullable=False),
+            sa.Column("lat", sa.Float(), nullable=True),
+            sa.Column("lng", sa.Float(), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        )
+
+    # 3. normalized_products
+    if not inspector.has_table("normalized_products"):
+        op.create_table(
+            "normalized_products",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("canonical_name", sa.String(300), nullable=False),
+            sa.Column("category", sa.String(50), nullable=True),
+            sa.Column("subcategory", sa.String(100), nullable=True),
+            sa.Column("brand", sa.String(200), nullable=True),
+            sa.Column("size", sa.String(50), nullable=True),
+            sa.Column("size_unit", sa.String(10), nullable=True),
+            sa.Column("upc_variants", sa.JSON(), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        )
+
+    # 4. purchases
+    if not inspector.has_table("purchases"):
+        op.create_table(
+            "purchases",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("user_id", sa.Text(), sa.ForeignKey("users.id"), nullable=False),
+            sa.Column("store_id", sa.Uuid(), sa.ForeignKey("stores.id"), nullable=False),
+            sa.Column("store_location_id", sa.Uuid(), sa.ForeignKey("store_locations.id"), nullable=True),
+            sa.Column("receipt_id", sa.String(200), nullable=False),
+            sa.Column("purchase_date", sa.Date(), nullable=False),
+            sa.Column("total", sa.Numeric(10, 2), nullable=False),
+            sa.Column("subtotal", sa.Numeric(10, 2), nullable=True),
+            sa.Column("tax", sa.Numeric(10, 2), nullable=True),
+            sa.Column("savings_total", sa.Numeric(10, 2), nullable=True),
+            sa.Column("source_url", sa.String(500), nullable=True),
+            sa.Column("raw_data", sa.JSON(), nullable=True),
+            sa.Column("ingested_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.UniqueConstraint("user_id", "store_id", "receipt_id", name="uq_purchase_receipt"),
+            sa.Index("ix_purchases_user_store", "user_id", "store_id"),
+        )
+
+    # 5. purchase_items
+    if not inspector.has_table("purchase_items"):
+        op.create_table(
+            "purchase_items",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("purchase_id", sa.Uuid(), sa.ForeignKey("purchases.id"), nullable=False),
+            sa.Column("product_name_raw", sa.String(300), nullable=False),
+            sa.Column("upc", sa.String(20), nullable=True),
+            sa.Column("quantity", sa.Numeric(10, 3), nullable=False),
+            sa.Column("unit_price", sa.Numeric(10, 2), nullable=False),
+            sa.Column("extended_price", sa.Numeric(10, 2), nullable=False),
+            sa.Column("regular_price", sa.Numeric(10, 2), nullable=True),
+            sa.Column("sale_price", sa.Numeric(10, 2), nullable=True),
+            sa.Column("coupon_discount", sa.Numeric(10, 2), nullable=True),
+            sa.Column("loyalty_discount", sa.Numeric(10, 2), nullable=True),
+            sa.Column("category_raw", sa.String(100), nullable=True),
+            sa.Column("normalized_product_id", sa.Uuid(), sa.ForeignKey("normalized_products.id"), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        )
+
+    # 6. coupons
+    if not inspector.has_table("coupons"):
+        op.create_table(
+            "coupons",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("store_id", sa.Uuid(), sa.ForeignKey("stores.id"), nullable=False),
+            sa.Column("normalized_product_id", sa.Uuid(), sa.ForeignKey("normalized_products.id"), nullable=True),
+            sa.Column("title", sa.String(300), nullable=False),
+            sa.Column("description", sa.String(1000), nullable=True),
+            sa.Column("discount_type", sa.String(20), nullable=False),
+            sa.Column("discount_value", sa.Numeric(10, 2), nullable=True),
+            sa.Column("min_purchase", sa.Numeric(10, 2), nullable=True),
+            sa.Column("valid_from", sa.Date(), nullable=True),
+            sa.Column("valid_to", sa.Date(), nullable=True),
+            sa.Column("requires_clip", sa.Boolean(), server_default=text("false"), nullable=False),
+            sa.Column("coupon_code", sa.String(100), nullable=True),
+            sa.Column("source_url", sa.String(500), nullable=True),
+            sa.Column("scraped_at", sa.DateTime(timezone=True), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        )
+
+    # 7. price_history
+    if not inspector.has_table("price_history"):
+        op.create_table(
+            "price_history",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("normalized_product_id", sa.Uuid(), sa.ForeignKey("normalized_products.id"), nullable=False),
+            sa.Column("store_id", sa.Uuid(), sa.ForeignKey("stores.id"), nullable=False),
+            sa.Column("observed_date", sa.Date(), nullable=False),
+            sa.Column("regular_price", sa.Numeric(10, 2), nullable=False),
+            sa.Column("sale_price", sa.Numeric(10, 2), nullable=True),
+            sa.Column("loyalty_price", sa.Numeric(10, 2), nullable=True),
+            sa.Column("coupon_price", sa.Numeric(10, 2), nullable=True),
+            sa.Column("source", sa.String(20), nullable=False),
+            sa.Column("purchase_item_id", sa.Uuid(), sa.ForeignKey("purchase_items.id"), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Index("ix_price_history_product_store_date", "normalized_product_id", "store_id", "observed_date"),
+        )
+
+    # 8. shrinkflation_events
+    if not inspector.has_table("shrinkflation_events"):
+        op.create_table(
+            "shrinkflation_events",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("normalized_product_id", sa.Uuid(), sa.ForeignKey("normalized_products.id"), nullable=False),
+            sa.Column("detected_date", sa.Date(), nullable=False),
+            sa.Column("old_size", sa.String(50), nullable=False),
+            sa.Column("new_size", sa.String(50), nullable=False),
+            sa.Column("old_unit", sa.String(10), nullable=True),
+            sa.Column("new_unit", sa.String(10), nullable=True),
+            sa.Column("price_at_old_size", sa.Numeric(10, 2), nullable=True),
+            sa.Column("price_at_new_size", sa.Numeric(10, 2), nullable=True),
+            sa.Column("confidence", sa.Numeric(3, 2), server_default=text("1.00"), nullable=False),
+            sa.Column("notes", sa.String(1000), nullable=True),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+        )
+
+    # 9. user_store_accounts
+    if not inspector.has_table("user_store_accounts"):
+        op.create_table(
+            "user_store_accounts",
+            sa.Column("id", sa.Uuid(), server_default=text("gen_random_uuid()"), primary_key=True),
+            sa.Column("user_id", sa.Text(), sa.ForeignKey("users.id"), nullable=False),
+            sa.Column("store_id", sa.Uuid(), sa.ForeignKey("stores.id"), nullable=False),
+            sa.Column("session_data", sa.JSON(), nullable=True),
+            sa.Column("session_expires_at", sa.DateTime(timezone=True), nullable=True),
+            sa.Column("last_sync_at", sa.DateTime(timezone=True), nullable=True),
+            sa.Column("status", sa.String(20), server_default=text("'active'"), nullable=False),
+            sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.UniqueConstraint("user_id", "store_id", name="uq_user_store_account"),
+        )
+
+
+def downgrade() -> None:
+    conn = op.get_bind()
+    inspector = sa.inspect(conn)
+
+    if inspector.has_table("user_store_accounts"):
+        op.drop_table("user_store_accounts")
+    if inspector.has_table("shrinkflation_events"):
+        op.drop_table("shrinkflation_events")
+    if inspector.has_table("price_history"):
+        op.drop_table("price_history")
+    if inspector.has_table("coupons"):
+        op.drop_table("coupons")
+    if inspector.has_table("purchase_items"):
+        op.drop_table("purchase_items")
+    if inspector.has_table("purchases"):
+        op.drop_table("purchases")
+    if inspector.has_table("normalized_products"):
+        op.drop_table("normalized_products")
+    if inspector.has_table("store_locations"):
+        op.drop_table("store_locations")
+    if inspector.has_table("stores"):
+        op.drop_table("stores")

api/src/cartsnitch_api/auth/dependencies.py

@@ -71,11 +71,14 @@ async def get_current_user(
     # 1. Check session cookie — prefer __Secure- variant (HTTPS) over plain (HTTP dev)
     cookie_token = request.cookies.get(SECURE_SESSION_COOKIE_NAME) or request.cookies.get(SESSION_COOKIE_NAME)
     if cookie_token:
-        token = cookie_token
+        # Better-Auth cookie format is "token.sessionId" — extract just the token part
+        token = cookie_token.split(".")[0] if "." in cookie_token else cookie_token
 
     # 2. Fall back to Bearer header
     if not token and credentials:
-        token = credentials.credentials
+        # Callers might pass the compound value here too
+        raw = credentials.credentials
+        token = raw.split(".")[0] if "." in raw else raw
 
     if not token:
         raise HTTPException(

api/src/cartsnitch_api/config.py

@@ -1,23 +1,25 @@
 import base64
 
-from pydantic import model_validator
+from pydantic import AliasChoices, Field, model_validator
 from pydantic_settings import BaseSettings
 
 
 class Settings(BaseSettings):
     model_config = {"env_prefix": "CARTSNITCH_"}
 
-    database_url: str = "postgresql+asyncpg://cartsnitch:cartsnitch@localhost:5432/cartsnitch"
+    database_url: str = Field(
+        default="postgresql+asyncpg://cartsnitch:cartsnitch@localhost:5432/cartsnitch",
+        validation_alias=AliasChoices("CARTSNITCH_DATABASE_URL", "DATABASE_URL"),
+    )
     redis_url: str = "redis://localhost:6379/0"
 
-    jwt_secret_key: str = "change-me-in-production"
+    jwt_secret_key: str
     jwt_algorithm: str = "HS256"
     jwt_access_token_expire_minutes: int = 15
     jwt_refresh_token_expire_days: int = 7
 
-    service_key: str = "change-me-in-production"
-    # Valid Fernet key for local dev — MUST be overridden in production
-    fernet_key: str = "7reF42nmTwbdN21PBoubGp7h_FU8qSimstmlaMLoRK8="
+    service_key: str
+    fernet_key: str
 
     auth_service_url: str = "http://auth:3001"
 
@@ -32,9 +34,26 @@ class Settings(BaseSettings):
     rate_limit_window_seconds: int = 60
     rate_limit_enabled: bool = True
 
+    _PLACEHOLDER_VALUES = {"change-me-in-production"}
+
     @model_validator(mode="after")
-    def validate_fernet_key(self):
-        """Validate fernet_key is a valid 32-byte url-safe base64 key at startup."""
+    def validate_secrets(self):
+        if not self.jwt_secret_key or self.jwt_secret_key in self._PLACEHOLDER_VALUES:
+            raise ValueError(
+                "CARTSNITCH_JWT_SECRET_KEY must be set to a secure value. "
+                'Generate one with: python -c "import secrets; print(secrets.token_urlsafe(32))"'
+            )
+        if not self.service_key or self.service_key in self._PLACEHOLDER_VALUES:
+            raise ValueError(
+                "CARTSNITCH_SERVICE_KEY must be set to a secure value. "
+                'Generate one with: python -c "import secrets; print(secrets.token_urlsafe(32))"'
+            )
+        if not self.fernet_key or self.fernet_key in self._PLACEHOLDER_VALUES:
+            raise ValueError(
+                "CARTSNITCH_FERNET_KEY must be set to a valid Fernet key. "
+                "Generate one with: python -c "
+                "'from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())'"
+            )
         try:
             decoded = base64.urlsafe_b64decode(self.fernet_key.encode())
             if len(decoded) != 32:
@@ -49,5 +68,12 @@ class Settings(BaseSettings):
             ) from None
         return self
 
+    @model_validator(mode="after")
+    def normalize_database_url(self):
+        """Normalize postgresql:// → postgresql+asyncpg:// for the asyncpg driver."""
+        if self.database_url.startswith("postgresql://"):
+            self.database_url = self.database_url.replace("postgresql://", "postgresql+asyncpg://", 1)
+        return self
+
 
 settings = Settings()

api/tests/conftest.py

@@ -19,6 +19,25 @@ from cartsnitch_api.database import get_db
 from cartsnitch_api.main import create_app
 from cartsnitch_api.models import Base
 
+TEST_JWT_SECRET = secrets.token_urlsafe(32)
+TEST_SERVICE_KEY = secrets.token_urlsafe(32)
+TEST_FERNET_KEY = "7reF42nmTwbdN21PBoubGp7h_FU8qSimstmlaMLoRK8="
+
+
+@pytest.fixture(autouse=True)
+def setup_test_settings():
+    original_jwt = cartsnitch_settings.jwt_secret_key
+    original_service = cartsnitch_settings.service_key
+    original_fernet = cartsnitch_settings.fernet_key
+    cartsnitch_settings.jwt_secret_key = TEST_JWT_SECRET
+    cartsnitch_settings.service_key = TEST_SERVICE_KEY
+    cartsnitch_settings.fernet_key = TEST_FERNET_KEY
+    yield
+    cartsnitch_settings.jwt_secret_key = original_jwt
+    cartsnitch_settings.service_key = original_service
+    cartsnitch_settings.fernet_key = original_fernet
+
+
 TEST_DATABASE_URL = "sqlite+aiosqlite:///:memory:"
 
 
@@ -60,7 +79,8 @@ async def db_engine():
     async with engine.begin() as conn:
         await conn.run_sync(Base.metadata.create_all)
         # Create Better-Auth tables (not managed by SQLAlchemy models)
-        await conn.execute(text("""
+        await conn.execute(
+            text("""
             CREATE TABLE IF NOT EXISTS sessions (
                 id TEXT PRIMARY KEY,
                 token TEXT NOT NULL UNIQUE,
@@ -71,8 +91,10 @@ async def db_engine():
                 created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
                 updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
             )
-        """))
-        await conn.execute(text("""
+        """)
+        )
+        await conn.execute(
+            text("""
             CREATE TABLE IF NOT EXISTS accounts (
                 id TEXT PRIMARY KEY,
                 user_id TEXT NOT NULL,
@@ -88,8 +110,10 @@ async def db_engine():
                 created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
                 updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
             )
-        """))
-        await conn.execute(text("""
+        """)
+        )
+        await conn.execute(
+            text("""
             CREATE TABLE IF NOT EXISTS verifications (
                 id TEXT PRIMARY KEY,
                 identifier TEXT NOT NULL,
@@ -98,7 +122,8 @@ async def db_engine():
                 created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL,
                 updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
             )
-        """))
+        """)
+        )
 
     yield engine
 
@@ -133,7 +158,9 @@ async def client(db_engine):
     app.dependency_overrides.clear()
 
 
-async def _create_test_user_and_session(client: AsyncClient, db_engine, **user_overrides) -> tuple[dict, str]:
+async def _create_test_user_and_session(
+    client: AsyncClient, db_engine, **user_overrides
+) -> tuple[dict, str]:
     """Create a test user and a valid session directly in the DB.
 
     Returns (user_dict, session_token).  Better-Auth stores the raw token

api/tests/test_auth/test_auth_endpoints.py

@@ -71,6 +71,56 @@ async def test_delete_me(client, auth_headers):
     assert resp.status_code == 404
 
 
+@pytest.mark.asyncio
+async def test_get_me_compound_cookie(client, db_engine):
+    """Compound cookie value (token.sessionId) must be parsed to extract the token part."""
+    from tests.conftest import _create_test_user_and_session
+
+    _, session_token = await _create_test_user_and_session(
+        client, db_engine, email="compound@example.com", display_name="Compound User"
+    )
+    compound = f"{session_token}.B0atkJCFxK1rZlwWPMK97nVO2LnyDun7"
+    resp = await client.get(
+        "/auth/me",
+        headers={"Cookie": f"better-auth.session_token={compound}"},
+    )
+    assert resp.status_code == 200
+    assert resp.json()["email"] == "compound@example.com"
+
+
+@pytest.mark.asyncio
+async def test_get_me_raw_token_cookie(client, db_engine):
+    """Raw token (no dot) in cookie must still work — regression guard."""
+    from tests.conftest import _create_test_user_and_session
+
+    _, session_token = await _create_test_user_and_session(
+        client, db_engine, email="rawcookie@example.com", display_name="Raw Cookie User"
+    )
+    resp = await client.get(
+        "/auth/me",
+        headers={"Cookie": f"better-auth.session_token={session_token}"},
+    )
+    assert resp.status_code == 200
+    assert resp.json()["email"] == "rawcookie@example.com"
+
+
+@pytest.mark.asyncio
+async def test_get_me_compound_bearer(client, db_engine):
+    """Compound Bearer token (token.sessionId) must be parsed to extract the token part."""
+    from tests.conftest import _create_test_user_and_session
+
+    _, session_token = await _create_test_user_and_session(
+        client, db_engine, email="compoundbearer@example.com", display_name="Compound Bearer User"
+    )
+    compound = f"{session_token}.B0atkJCFxK1rZlwWPMK97nVO2LnyDun7"
+    resp = await client.get(
+        "/auth/me",
+        headers={"Authorization": f"Bearer {compound}"},
+    )
+    assert resp.status_code == 200
+    assert resp.json()["email"] == "compoundbearer@example.com"
+
+
 @pytest.mark.asyncio
 async def test_expired_session_rejected(client, db_engine):
     """Expired sessions must be rejected."""

api/tests/test_config.py

@@ -0,0 +1,48 @@
+"""Tests for Settings config, specifically the database_url env var fallback."""
+
+import os
+
+from cartsnitch_api.config import Settings
+
+
+def test_database_url_prefers_cartsnitch_prefix():
+    """CARTSNITCH_DATABASE_URL takes precedence over DATABASE_URL."""
+    env = {
+        "CARTSNITCH_DATABASE_URL": "postgresql+asyncpg://user1:pass1@host1:5432/db1",
+        "DATABASE_URL": "postgresql://user2:pass2@host2:5432/db2",
+    }
+    settings = Settings(**env)
+    assert settings.database_url == "postgresql+asyncpg://user1:pass1@host1:5432/db1"
+
+
+def test_database_url_falls_back_to_database_url():
+    """When CARTSNITCH_DATABASE_URL is absent, DATABASE_URL is accepted."""
+    env = {
+        "DATABASE_URL": "postgresql://user:pass@dbhost:5432/mydb",
+    }
+    settings = Settings(**env)
+    assert settings.database_url == "postgresql+asyncpg://user:pass@dbhost:5432/mydb"
+
+
+def test_database_url_normalizes_plain_postgresql_prefix():
+    """DATABASE_URL with plain postgresql:// is normalized to postgresql+asyncpg://."""
+    env = {
+        "DATABASE_URL": "postgresql://cartsnitch:cartsnitch@localhost:5432/cartsnitch",
+    }
+    settings = Settings(**env)
+    assert settings.database_url == "postgresql+asyncpg://cartsnitch:cartsnitch@localhost:5432/cartsnitch"
+
+
+def test_database_url_preserves_asyncpg_prefix():
+    """CARTSNITCH_DATABASE_URL with postgresql+asyncpg:// is left unchanged."""
+    env = {
+        "CARTSNITCH_DATABASE_URL": "postgresql+asyncpg://cartsnitch:cartsnitch@localhost:5432/cartsnitch",
+    }
+    settings = Settings(**env)
+    assert settings.database_url == "postgresql+asyncpg://cartsnitch:cartsnitch@localhost:5432/cartsnitch"
+
+
+def test_database_url_default():
+    """When neither env var is set, the hardcoded default is used."""
+    settings = Settings()
+    assert settings.database_url == "postgresql+asyncpg://cartsnitch:cartsnitch@localhost:5432/cartsnitch"