When I joined the company the backend ran on a fleet of EC2 instances sized for peak traffic, sitting at 15% CPU utilisation most of the time. Scaling was manual — someone would notice latency going up, SSH into a box to check what was happening, then provision more capacity if needed. Deployments required coordination to drain the load balancer and restart services one by one. Migrating to ECS Fargate with autoscaling was the single biggest infrastructure improvement we made: costs dropped 35%, deployments became zero-downtime, and on-call became less stressful. Why ECS Fargate Over EC2-Backed ECS ECS can run on two launch types: EC2 (you manage the instances) and Fargate (AWS manages the compute). I chose Fargate for three reasons: No instance management : no more AMI updates, no instance type selection, no patching Bin packing is AWS's problem : with EC2-backed ECS you need the right EC2 instance size to fit your tasks efficiently. Fargate handles this transparently. Pe...