How the software you use every day was actually built.
Practical guides on architecture and AI cost, plus five real product stories — the infrastructure decisions made early, or made too late, that shaped what they became. Same lens we use on every Yogreet build: what would this have cost to get right from day one?
How to reduce AI API & token costs: a practical guide
The four levers that actually move an AI bill — caching, routing, batching, output discipline — ranked by impact, with the quality trade-offs spelled out.
Microservices vs monolith for a startup: how to actually decide
Not a religious war — a staging decision. When a modular monolith wins, the three signals that justify a split, and how to migrate without a rewrite.
How much does it cost to scale an AI app?
The real cost drivers — tokens, infrastructure, data — why per-user cost creeps up, and how to keep it flat from 100 to 100,000 users.
Why startups end up rewriting their architecture (and how to avoid it)
The four causes of the expensive rewrite that lands right when growth works — and how designing clean seams early avoids it entirely.
13 people, one server, a billion-dollar app: the Instagram engineering story
How a tiny team avoided a rewrite by designing their database to be shard-friendly before they ever needed to shard it.
50 engineers, 2 billion users: how WhatsApp mastered infrastructure efficiency
WhatsApp didn't out-hire its way to scale. It out-architected everyone else's headcount with one unfashionable language choice.
The three-day outage that rebuilt Netflix from the ground up
A single database corruption in 2008 triggered a seven-year, full-stack rebuild — the most expensive "re-architecture spike" in tech history.
The game that failed twice — then became Slack
The product Tiny Speck spent years building wasn't the one that mattered. The internal tool built "just to get by" was.
Seven lines of code: how Stripe built infrastructure-first from day one
The one story on this list where nobody had to learn the lesson the expensive way — because the architecture was the product.