throw in (one's) lot

Translations
вложиться (в чью-то) судьбу
After years of working alone, she decided to throw in her lot with a startup company.
После многих лет работы в одиночку она решила вложиться в судьбу стартапа.
Definitions
To decide to join or align oneself with a person, group, or cause, often by sharing their risks, fortunes, or fate.