I Passed AZ-900 and Built a Quiz App with React, TypeScript and Supabase to Prepare

I'm officially Microsoft Certified: Azure Fundamentals! ☁️

I'm a self-taught developer focused on backend engineering. I took the AZ-900 exam to understand the cloud platform behind so many modern systems: compute, networking, storage, identity, security, and how cloud services are priced and governed.

To prepare, I joined the Power Learn Project Vibe Coding Hackathon (AZ-900 Exam Prep Edition) and used it to build something I could study with.

What I built

Smart Quiz Builder is an unofficial AZ-900 practice app. You answer exam-style questions and get an explanation for each answer, so you learn why an answer is right or wrong instead of memorising it.

🔗 Live demo: https://az900-smart-quiz.vercel.app
💻 Code: https://github.com/cyn4sh/az900-smart-quiz

The stack

• React + TypeScript (Vite): the quiz flow, results screen and history view.
• Supabase: anonymous auth, so anyone can use the app without signing up, plus storage for quiz attempts.
• Vercel: deployment.
• Cursor: my AI coding tool for the hackathon.

How I approached it

• Questions live in a typed file, not the database. The question set sits in a typed TypeScript file, and Supabase only stores attempts. That keeps the data model simple and the questions easy to review and edit.
• I reviewed everything the AI generated. I built the app in chunks with Cursor and checked each chunk before moving on, making sure the build and lint passed. Vibe coding is fast, but you still own the code.
• I designed before I built. I settled the look and architecture before opening the editor: a calm dark "late-night study" theme, mobile-first, with a teal accent for correct answers and coral for wrong ones.

What I learned

Building a study tool while studying for the exam made the concepts stick. Writing questions and explanations forced me to understand each topic well enough to explain it.

What's next

AZ-900 is a fundamentals cert, so I see it as a foundation, not a finish line. Next, I'm going deeper into backend development and infrastructure, building projects that put these cloud concepts into practice.

Credential

Verify my certification here: https://learn.microsoft.com/api/credentials/share/en-gb/Ashfall-1799/BEC3B0858B5CEEA1?sharingId=CAF4767643DF5F26

If you're preparing for AZ-900, try the quiz app and tell me what you think. 🙌