MERN bundles MongoDB, Express, React and Node into a single JavaScript stack, and it has become the standard training package for career switchers in India. That popularity cuts both ways: the openings are real, particularly in startups, agencies and smaller product companies, but the candidate supply is enormous. What separates hired candidates from the rest is almost never the course they took — it is whether they can show a deployed application with authentication, payments or file handling that they debugged themselves.