Frontend developers often face a common bottleneck: waiting for the backend API to be ready. DoppelAPI solves this by instantly creating a "Digital Twin" of your future backend directly from your OpenAPI (Swagger) definition. Unlike traditional mock servers that return static, repetitive data, DoppelAPI uses AI-driven data generation to serve realistic, schema-compliant responses (emails, UUIDs, avatars, etc.) on the fly. It feels like interacting with a real production database.