diff --git a/pyproject.toml b/pyproject.toml
index f80c124..780594a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "pytest-mock-resources"
-version = "2.6.8"
+version = "2.6.9"
 description = "A pytest plugin for easily instantiating reproducible mock resources."
 authors = [
     "Omar Khan <oakhan3@gmail.com>",
diff --git a/src/pytest_mock_resources/container/postgres.py b/src/pytest_mock_resources/container/postgres.py
index f6d739d..7aff7de 100644
--- a/src/pytest_mock_resources/container/postgres.py
+++ b/src/pytest_mock_resources/container/postgres.py
@@ -107,7 +107,7 @@ def get_sqlalchemy_engine(
         database=database_name,
     )
 
-    if getattr(url.get_dialect(), "is_async"):
+    if getattr(url.get_dialect(), "is_async", None):
         from sqlalchemy.ext.asyncio import create_async_engine
 
         engine = create_async_engine(url, **engine_kwargs, isolation_level=isolation_level)
diff --git a/src/pytest_mock_resources/fixture/postgresql.py b/src/pytest_mock_resources/fixture/postgresql.py
index 5748930..253da24 100644
--- a/src/pytest_mock_resources/fixture/postgresql.py
+++ b/src/pytest_mock_resources/fixture/postgresql.py
@@ -109,14 +109,18 @@ async def _async(*_, pmr_postgres_container, pmr_postgres_config):
 
 def _sync_fixture(pmr_config, engine_manager_kwargs, engine_kwargs):
     root_engine = cast(Engine, get_sqlalchemy_engine(pmr_config, pmr_config.root_database))
-    retry(root_engine.connect, retries=DEFAULT_RETRIES)
+    conn = retry(root_engine.connect, retries=DEFAULT_RETRIES)
+    conn.close()
+    root_engine.dispose()
 
+    root_engine = cast(Engine, get_sqlalchemy_engine(pmr_config, pmr_config.root_database))
     with root_engine.connect() as root_conn:
         with root_conn.begin() as trans:
             template_database, template_manager, engine_manager = create_engine_manager(
                 root_conn, **engine_manager_kwargs
             )
             trans.commit()
+    root_engine.dispose()
 
     if template_manager:
         assert template_database
@@ -132,10 +136,12 @@ def _sync_fixture(pmr_config, engine_manager_kwargs, engine_kwargs):
 
     # Everything below is normal per-test context. We create a brand new database/engine/manager
     # distinct from what might have been used for the template database.
+    root_engine = cast(Engine, get_sqlalchemy_engine(pmr_config, pmr_config.root_database))
     with root_engine.connect() as root_conn:
         with root_conn.begin() as trans:
             database_name = _produce_clean_database(root_conn, createdb_template=template_database)
             trans.commit()
+    root_engine.dispose()
 
     engine = get_sqlalchemy_engine(pmr_config, database_name, **engine_kwargs)
     yield from engine_manager.manage_sync(engine)