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Insights, tutorials, and career tips from the engineering community
Imagine you're using Uber. You request a ride. Within seconds, your request reaches an available driver near you. But here's the interesting question. How did Uber know which driver service to contact?
Imagine you're scrolling through your Instagram feed. You like a post. Your friend refreshes their phone immediately. For a few seconds... they still don't see your like. Did the system lose your data? No.
Imagine you're transferring ₹10,000 from your bank account to your friend's account. The process looks simple. Your account balance decreases. Your friend's balance increases. Now imagine something goes wrong halfway through. Your account is debited. But your friend's account is never credited because the database crashed. The money disappears.
One of the most common interview questions is: "What's the difference between Authentication and Authorization?" Surprisingly, many developers use these terms interchangeably. But they are not the same thing.
Senior interview answers that sound like experience, not flashcards: closures, event loop, prototypes, async pitfalls, and how to say "I do not know" without torpedoing the loop.
MongoDB, Express, React, and Node.js end to end: what to learn in order, starter projects that teach real skills, and mistakes to avoid when you deploy.
From BSON basics to production MERN stacks: schema design, indexing, aggregation, transactions, Atlas, and mistakes Node developers make when escaping SQL habits.
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