# Sarwagya · Eng

> Long-form writing on security, systems engineering, software architecture, and building software that lasts.

The engineering side of sarwagya.wtf. Long-form notes on protocols,
provenance, cryptography, and the pieces of infrastructure I keep
finding myself needing to build from scratch.

## Essays

- [Why I Killed an Email Rendering SaaS That Actually Worked](https://eng.sarwagya.wtf/learnings/why-i-killed-an-email-rendering-saas): It worked. It was cheap to run. I killed it anyway. This is the engineering story behind that decision.
- [What I Learnt About SaaS Cost and Architecture Relationships](https://eng.sarwagya.wtf/learnings/what-i-learnt-about-saas-costs): I wanted to build a $9.99 email testing SaaS. Then I discovered I was actually building a distributed hardware lab.
- [The verifier must outlive the product](https://eng.sarwagya.wtf/learnings/the-verifier-must-outlive-the-product): I shipped four packages in three days. The strangest one was supposed to be a TypeScript library — until I noticed that by the time I stopped, I was no longer designing a package. I was designing for the day it no longer existed.
- [What security audits taught me about writing software](https://eng.sarwagya.wtf/learnings/what-security-audits-taught-me-about-software): A year of reading other people's code for a living changes how you write your own. Notes on threat models, boring failure modes, and why the most secure code is usually the most legible.

## Also

- [Home](https://eng.sarwagya.wtf): the essay index and the author's bio in one page