It's important to not confuse Lambda for Lambda@Edge. Lambda can be executed in a total of 18 AWS regions (if you don't count GovCloud). More importantly, actually running your code in every region would be somewhat tricky, their architecture is built around you deploying to each individually.

Lambda@Edge does run on their CDN nodes, but it isn't quite for general-purpose compute, there's a long list of restrictions you can find here: https://docs.aws.amazon.com/AmazonCloudFront/latest/Develope...

If you're interested in the performance differences, I ran some comparisons using Catchpoint a while ago: https://blog.cloudflare.com/serverless-performance-compariso...

Lambda and Lambda@Edge also deal with things like cold-starts which impact performance irrespective of the breadth of the network. You can see some of those numbers here: https://serverless-benchmark.com/

I mentioned Lambda@Edge, but I knew less about that; I'll add a note and see if I can find a CloudFront map, thank you!

EDIT: Fixed, thank you! I meant to double check this and just forgot before hitting publish :(

I was super excited to try out Lambda@Edge with Rust a few weeks ago but discovered that right now, Lambda@Edge only supports Node.js. It's a pretty major limitation of the platform.

(Although since Rust can compile to WASM, it might be possible to write Rust, compile it to WASM, load that WASM in Node and run that on Lambda@Edge.)