Backend developers build the APIs, services and data models that power applications. Typical work includes designing endpoints, writing business logic, optimising SQL queries, handling authentication and adding tests and monitoring. Employers usually expect one server-side language (Node.js, Python, Java, PHP or Go), a database (MySQL or PostgreSQL) and familiarity with Git and cloud basics. Salaries range from ₹30,000 to ₹70,000 per month for mid-level engineers. Ask whether the team owns production support and on-call rotations before accepting a role.