@lars64 What exactly did you change? Did you add a new database connection to config/database.php and specify that in your phpunit.xml? E.g. in config/database.php
'sqlite_testing' => [
'driver' => 'sqlite',
'database' => database_path('testing.sqlite'),
'prefix' => '',
],
and in phpunit.xml
<env name="DB_CONNECTION" value="sqlite_testing"/>
Then just migrate your database ...
php artisan migrate --database=sqlite_testing
... and phpunit uses that database.