There are a couple of great anecdotes about Glass working at other jobs while starting out as a composer, one involving the art critic of Time magazine and another about driving a taxi.
'Glass understood that he had finally arrived as a composer when a woman tapped on the side of his cab and told him “you have the same name as a very famous composer.”
https://interlude.hk/philip-glass-composer-taxi-driver/
'Glass understood that he had finally arrived as a composer when a woman tapped on the side of his cab and told him “you have the same name as a very famous composer.”