A friend in the tech group asked me how I handled observability and security. I answered, the conversation drifted to stack choice, then to why not Kubernetes, then to when it's worth breaking up the monolith. He suggested I write about it. So here it goes. The context I run a SaaS that automates TikTok Ads campaign management for agencies. Each customer has N Business Centers → N Advertiser Accounts → N Campaigns → N Ad Groups → N Ads. Today's numbers: R$ 87k in MRR R$ 1M in ARR More than 7 million requests per day against the TikTok API 600+ endpoints mapped Everything in a Laravel 12 monolith I'm a solo dev. Rule number 1: less is more Every choice I'm about to describe comes from a single constraint: I don't have a team . That changes everything. One more tool is one more tool to configure, monitor, update, and debug at 3 a.m. So my criteria are always: Does the tool solve a real problem I have today? Does it add more complexity than the pain it removes? If it breaks tomorrow, can I fix it on my own?…