22 real interview questions and 8 fully solved DataWeave 2.0 challenges, built around actual production scenarios — not textbook definitions. Covers Mule 4 fundamentals, DataWeave, error handling, API-led connectivity, and deployment, with a dedicated section on real failures: Scatter-Gather routes breaking under load, database timeouts, JWT expiry mid-transaction, batch job recovery. Banking, insurance, and telecom domain examples throughout. Each answer includes the scenario, the trade-off, and an interview tip you can actually use.