FAQ
Backend development
18 questions and answers about Backend development, from Muhammad Shahid, Senior AI Software Engineer and Backend Developer.
Backend development
1. Which backend technologies do you use?
Node.js and Express.js for APIs, MongoDB with Mongoose for data, Redis for caching, REST APIs with JWT authentication, EJS for server-rendered pages, and Heroku, VPS servers or Netlify for deployment.
2. Are you a Node.js developer?
Yes. Node.js is my main backend language. I have used it in production at Quecko Inc. and Dlux Soft for products with millions of users, including DOP, TheCryptoBasic and CV Maker.
3. Do you build REST APIs?
Yes. I build production Express and MongoDB REST APIs with request validation, centralised error handling, logging, JWT authentication, caching and pagination.
4. Do you work with MongoDB?
Yes, it is my main database. I design schemas and compound indexes, write aggregation pipelines and use Mongoose. I also hold the MongoDB and Mongoose certification from MongoDB University.
5. How do you use Redis?
Mainly to cache read-heavy routes. At DOP I added a Redis caching layer together with new MongoDB indexes, which brought API timeouts and database CPU load under control at 300M+ users.
6. Can you fix login and session problems?
Yes. At TheCryptoBasic users were being logged out at random. I traced it to incorrect JWT expiry and refresh-token handling and rewrote the session flow so sessions now persist as intended.
7. Can you build the backend for a mobile app?
Yes. I developed the backend of CV Maker – Resume Builder, an Android app on Google Play with 1M+ users worldwide, and worked with the mobile and design teams to ship its releases.
8. Can you integrate third-party APIs?
Yes. I built the live market-data pipeline at TheCryptoBasic, connected 5 RPC providers at DOP, and build API and LLM integrations for AI agents.
9. Do you work with real-time data and WebSockets?
Yes. TheCryptoBasic serves live market data to 2M+ users, and my open-source project cmcprice-Websocket streams live crypto prices over WebSockets.
10. Where do you deploy backends?
Node.js backends on Heroku or VPS servers, and static and Next.js sites, like this one, on Netlify.
11. Can you fix payment and transaction failures?
Yes. At Quecko I investigated user-reported payment and transaction failures, traced the root causes, shipped fixes on tight timelines, restored reliable payments and added monitoring and error alerts to catch failures early.
12. How do you make a backend reliable?
Request validation, centralised error handling, logging, monitoring and error alerts, and testing before every release. At Dlux Soft this approach reduced production errors.
13. Can you add monitoring and error alerts?
Yes. I add monitoring and alerts as part of every fix, so the next failure is caught by the system instead of being reported by users.
14. Can you build a full-stack app on your own?
Yes. I built New-Waffle, an NFT raffle web application, end to end on my own: the raffle logic, the backend and the web client, deployed solo.
15. Do you build internal tools?
Yes. Two of my open-source tools are mongodb-data-exporter, which exports every collection in a MongoDB database to its own JSON file, and video-splitter-with-text, which splits videos and burns in text overlays.
16. Can you work on a backend someone else built?
Yes, that is most of my work. I have taken over live products with millions of users and fixed their performance, session and payment bugs without rewriting them.
17. Do you use NestJS?
Yes. I build Node.js backends with NestJS when a project benefits from its modules and dependency injection, and with Express when a lighter setup fits better.
18. Do you build GraphQL APIs?
Yes. I build GraphQL APIs as well as REST APIs, and choose between them based on how the clients need to fetch data.