Personal engineering journal

Shivansh Kumar

Building software. Breaking down systems.
Understanding what happens underneath.

The AWS Bill That Taught Me More Than Any Cloud Course

A small architecture, a surprisingly large bill, and the lesson hidden inside every invisible data path.

AI is not simply replacing junior developers—it is changing the work through which they learn. What should entry-level engineers master now?

CPU says 20%. Memory looks comfortable. The application is still slow because host health and application health are different systems.

16 posts

I trace software past the happy path—into the systems, trade-offs, and failures that make it real.

Selected field notes

When one engineer becomes critical infrastructure, expertise has turned into organizational risk.

Why race conditions disappear under a debugger—and how to investigate a system without changing its timing.

It happens earlier than you think: the moment correctness depends on two machines agreeing across an unreliable network.

THE CODE WORKS.