Online Learning Platform

Build a production-grade learning platform with instructor publishing workflows, student enrollment, paid access, video and document delivery, quizzes, certificates, and progress tracking. Define explicit models for course content, enrollments, entitlements, assessments, completion state, and certificates. Enforce role-based controls for students, instructors, and administrators. Include observability for media delivery and payment failures, secure access to premium content, idempotent certificate issuance, auditability for grading and content changes, and a migration plan for evolving course structures without breaking learner progress.