diff --git a/tests/unit/hooks/test_postgresql.py b/tests/unit/hooks/test_postgresql.py
new file mode 100644
index 0000000..3d8cf90
--- /dev/null
+++ b/tests/unit/hooks/test_postgresql.py
@@ -0,0 +1,155 @@
+import pytest
+from flexmock import flexmock
+
+from borgmatic.hooks import postgresql as module
+
+
+def test_dump_databases_runs_pg_dump_for_each_database():
+    databases = [{'name': 'foo'}, {'name': 'bar'}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+
+    for name in ('foo', 'bar'):
+        flexmock(module).should_receive('execute_command').with_args(
+            (
+                'pg_dump',
+                '--no-password',
+                '--clean',
+                '--file',
+                'databases/localhost/{}'.format(name),
+                '--format',
+                'custom',
+                name,
+            ),
+            extra_environment=None,
+        ).once()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=False)
+
+
+def test_dump_databases_with_dry_run_skips_pg_dump():
+    databases = [{'name': 'foo'}, {'name': 'bar'}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+    flexmock(module).should_receive('execute_command').never()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=True)
+
+
+def test_dump_databases_without_databases_does_not_raise():
+    module.dump_databases([], 'test.yaml', dry_run=False)
+
+
+def test_dump_databases_with_invalid_database_name_raises():
+    databases = [{'name': 'heehee/../../etc/passwd'}]
+
+    with pytest.raises(ValueError):
+        module.dump_databases(databases, 'test.yaml', dry_run=True)
+
+
+def test_dump_databases_runs_pg_dump_with_hostname_and_port():
+    databases = [{'name': 'foo', 'hostname': 'database.example.org', 'port': 5433}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+
+    flexmock(module).should_receive('execute_command').with_args(
+        (
+            'pg_dump',
+            '--no-password',
+            '--clean',
+            '--file',
+            'databases/database.example.org/foo',
+            '--host',
+            'database.example.org',
+            '--port',
+            '5433',
+            '--format',
+            'custom',
+            'foo',
+        ),
+        extra_environment=None,
+    ).once()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=False)
+
+
+def test_dump_databases_runs_pg_dump_with_username_and_password():
+    databases = [{'name': 'foo', 'username': 'postgres', 'password': 'trustsome1'}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+
+    flexmock(module).should_receive('execute_command').with_args(
+        (
+            'pg_dump',
+            '--no-password',
+            '--clean',
+            '--file',
+            'databases/localhost/foo',
+            '--username',
+            'postgres',
+            '--format',
+            'custom',
+            'foo',
+        ),
+        extra_environment={'PGPASSWORD': 'trustsome1'},
+    ).once()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=False)
+
+
+def test_dump_databases_runs_pg_dump_with_format():
+    databases = [{'name': 'foo', 'format': 'tar'}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+
+    flexmock(module).should_receive('execute_command').with_args(
+        (
+            'pg_dump',
+            '--no-password',
+            '--clean',
+            '--file',
+            'databases/localhost/foo',
+            '--format',
+            'tar',
+            'foo',
+        ),
+        extra_environment=None,
+    ).once()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=False)
+
+
+def test_dump_databases_runs_pg_dump_with_options():
+    databases = [{'name': 'foo', 'options': '--stuff=such'}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+
+    flexmock(module).should_receive('execute_command').with_args(
+        (
+            'pg_dump',
+            '--no-password',
+            '--clean',
+            '--file',
+            'databases/localhost/foo',
+            '--format',
+            'custom',
+            '--stuff=such',
+            'foo',
+        ),
+        extra_environment=None,
+    ).once()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=False)
+
+
+def test_dump_databases_runs_pg_dumpall_for_all_databases():
+    databases = [{'name': 'all'}]
+    flexmock(module.os.path).should_receive('expanduser').and_return('databases')
+    flexmock(module.os).should_receive('makedirs')
+
+    flexmock(module).should_receive('execute_command').with_args(
+        ('pg_dumpall', '--no-password', '--clean', '--file', 'databases/localhost/all'),
+        extra_environment=None,
+    ).once()
+
+    module.dump_databases(databases, 'test.yaml', dry_run=False)