Pretty nice! I like the music choice and the visual artwork. The spaceships look like spaceships, the bullets are visible and clear, the hitboxes aren't too big... It's been quite fun to play, goob job! :)
Next steps would be to create a scenario, endless games are fun but they can get boring once a certain level of skill has been reached (I see you put various ship patterns and bosses, that's a good idea).