diff --git a/requirements-db.txt b/requirements-db.txt
--- a/requirements-db.txt
+++ b/requirements-db.txt
@@ -1,4 +1,4 @@
 # requirements for swh.core.db
 psycopg2
 typing-extensions
-pytest-postgresql
+
diff --git a/requirements-test-db.txt b/requirements-test-db.txt
--- a/requirements-test-db.txt
+++ b/requirements-test-db.txt
@@ -1 +1 @@
-
+pytest-postgresql
diff --git a/swh/core/db/pytest_plugin.py b/swh/core/db/pytest_plugin.py
--- a/swh/core/db/pytest_plugin.py
+++ b/swh/core/db/pytest_plugin.py
@@ -10,14 +10,20 @@
 
 import psycopg2
 import pytest
-from pytest_postgresql import factories
-from pytest_postgresql.janitor import DatabaseJanitor, Version
 
 from swh.core.utils import numfile_sortkey as sortkey
 
 logger = logging.getLogger(__name__)
 
 
+try:
+    from pytest_postgresql import factories
+    from pytest_postgresql.janitor import DatabaseJanitor, Version
+except ImportError:
+    error_msg = "The module pytest_plugin requires dependency pytest-postgresql module"
+    raise EnvironmentError(error_msg)
+
+
 class SWHDatabaseJanitor(DatabaseJanitor):
     """SWH database janitor implementation with a a different setup/teardown policy than
     than the stock one. Instead of dropping, creating and initializing the database for