diff --git a/src/auth/service.py b/src/auth/service.py
index 0417952..f156a9d 100644
--- a/src/auth/service.py
+++ b/src/auth/service.py
@@ -19,6 +19,7 @@ from fastapi.security import OpenIdConnect
 from src.auth.exceptions import UnauthorizedException
 from src.auth.config import auth_settings
 from src.user.service import add_user_to_db
+from src.database import db_dependency
 
 
 oidc = OpenIdConnect(openIdConnectUrl=auth_settings.OIDC_CONFIG)
@@ -28,7 +29,7 @@ def get_dev_user():
 	return {"db_id": 1}
 
 
-async def get_current_user(oidc_auth_string: oidc_dependency) -> dict[str, Any]:
+async def get_current_user(oidc_auth_string: oidc_dependency, db: db_dependency) -> dict[str, Any]:
 	config_url = urlopen(auth_settings.OIDC_CONFIG)
 	config = json.loads(config_url.read())
 	jwks_uri = config["jwks_uri"]
@@ -51,7 +52,7 @@ async def get_current_user(oidc_auth_string: oidc_dependency) -> dict[str, Any]:
 		claims_requests.validate(token.claims)
 	except ExpiredTokenError:
 		raise UnauthorizedException(message="Token is expired")
-	db_id = await add_user_to_db(token.claims)
+	db_id = await add_user_to_db(db, token.claims)
 
 	token.claims["db_id"] = db_id
 
diff --git a/src/config.py b/src/config.py
index 120354e..98f782a 100644
--- a/src/config.py
+++ b/src/config.py
@@ -48,6 +48,9 @@ _QUOTED_DATABASE_PASSWORD = parse.quote_plus(str(_DATABASE_CREDENTIAL_PASSWORD))
 
 SQLALCHEMY_DATABASE_URI = SecretStr(f"postgresql+psycopg://{_DATABASE_CREDENTIAL_USER}:{_QUOTED_DATABASE_PASSWORD}@{DATABASE_HOSTNAME}:{DATABASE_PORT}/{DATABASE_NAME}")
 
+if settings.ENVIRONMENT == Environment.TESTING:
+    SQLALCHEMY_DATABASE_URI = SecretStr("sqlite:///:memory:")
+
 app_configs: dict[str, Any] = {"title": "App API"}
 if settings.ENVIRONMENT.is_deployed:
     app_configs["root_path"] = f"/v{settings.APP_VERSION}"
diff --git a/src/database.py b/src/database.py
index 819faeb..673af86 100644
--- a/src/database.py
+++ b/src/database.py
@@ -7,13 +7,19 @@ Exports:
 """
 from typing import Annotated
 from sqlalchemy import create_engine
-from sqlalchemy.orm import declarative_base, sessionmaker, Session
+from sqlalchemy.orm import DeclarativeBase, sessionmaker, Session
 
 from fastapi import Depends
 
-from src.config import SQLALCHEMY_DATABASE_URI
+from src.constants import Environment
+from src.config import SQLALCHEMY_DATABASE_URI, settings as global_settings
 
-engine = create_engine(SQLALCHEMY_DATABASE_URI.get_secret_value())
+if global_settings.ENVIRONMENT == Environment.TESTING:
+	connect_args = {"check_same_thread": False}
+else:
+	connect_args = {}
+
+engine = create_engine(SQLALCHEMY_DATABASE_URI.get_secret_value(), connect_args=connect_args)
 
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
@@ -30,4 +36,5 @@ def get_db():
 
 
 db_dependency = Annotated[Session, Depends(get_db)]
-Base = declarative_base()
+class Base(DeclarativeBase):
+	pass
diff --git a/src/main.py b/src/main.py
index a5ed717..d3fc945 100644
--- a/src/main.py
+++ b/src/main.py
@@ -8,6 +8,7 @@ from fastapi import FastAPI
 from starlette.middleware.sessions import SessionMiddleware
 from starlette.middleware.cors import CORSMiddleware
 
+from src.constants import Environment
 from src.config import settings
 from src.api import api_router
 
@@ -66,7 +67,7 @@ app.add_middleware(
 	allow_headers=settings.CORS_HEADERS,
 )
 
-if settings.ENVIRONMENT == "local" and settings.DISABLE_AUTH:
+if settings.DISABLE_AUTH and (settings.ENVIRONMENT == Environment.LOCAL or settings.ENVIRONMENT == Environment.TESTING):
 	app.dependency_overrides[get_current_user] = get_dev_user
 
 
diff --git a/src/user/service.py b/src/user/service.py
index 3d42574..e072251 100644
--- a/src/user/service.py
+++ b/src/user/service.py
@@ -6,29 +6,31 @@ Exports:
 """
 from typing import Any
 
-from src.database import get_db
+from sqlalchemy.orm import Session
+
 from src.exceptions import UnprocessableContentException
 
 from src.user.schemas import OIDCUser
 from src.user.models import User
 
 
-async def add_user_to_db(user_claims: dict[str, Any]) -> int:
+async def add_user_to_db(db: Session, user_claims: dict[str, Any]) -> int:
 	try:
 		valid_user = OIDCUser(first_name=user_claims["given_name"], last_name=user_claims["family_name"], email=user_claims["email"], oidc_id=user_claims["sub"])
 	except Exception as e:
 		print(e)
 		raise UnprocessableContentException("Invalid or missing OIDC data")
 
-	db = next(get_db())
 	db_user = db.query(User).filter(User.oidc_id == valid_user.oidc_id).first()
 
 	if not db_user:
 		user_model = User(**valid_user.model_dump())
 		db.add(user_model)
+		user_id = user_model.id
 		db.commit()
-		return user_model.id
+		return user_id
 	else:
+		user_id = db_user.id
 		change = False
 		if db_user.first_name != valid_user.first_name:
 			db_user.first_name = valid_user.first_name
@@ -39,4 +41,4 @@ async def add_user_to_db(user_claims: dict[str, Any]) -> int:
 		if change:
 			db.add(db_user)
 			db.commit()
-		return db_user.id
+		return user_id