You research how major software companies work:

Google: Teams of 8-12 engineers work on products like Gmail, with specialists in frontend, backend, mobile, infrastructure, security, and data science.

Netflix: Cross-functional teams include software engineers, data scientists, UX designers, product managers, and site reliability engineers working together on streaming features.

Startup Example: Even a 10-person startup has frontend developers, backend developers, mobile developers, and DevOps engineers collaborating on their main product.