Container pulls are slow. Lambda starts fast as it's not unpacking your container to a local disk on every start.

I can't tell you why Fargate is so slow, but the reason Lambda containers are so fast is because it doesn't actually load the image. It loads a manifest of the layers and the files in each, and then each file is loaded on-demand from a multi-tier cache. 90% of the image is never loaded, and 90% of the remainder is served from local cache. It's a pretty cool architecture.

Confirming, I worked directly on fargate.

Fargate does not use firecracker. It was used for some internal workloads but was being migrated off at the end of 2025.