So, how do you actually deal with secret keys and things when you're working with microservices?

hey everyone, im curious about the best practices for managing sensitive information like api keys, database credentials, and certificates across a growing microservices architecture. are you folks using dedicated secrets management tools like hashicorp vault or aws secrets manager? or do you have custom solutions? what are the main challenges youve encountered, and how did you overcome them? looking forward to hearing your thoughts and experiences!