I like Lambda for a lot of things, but there s a very specific point where it stops feeling elegant.
Usually it starts with something like:
a job that runs too long
a workflow that should keep going in the background
a task that needs better isolation or custom runtime behavior
a system that starts needing cron, retries, webhooks, logs, and routing in one place
And then the answer often becomes: move to Fargate, ECS, Step Functions, EC2, or stitch multiple services together.