Py 3.11 is more performant than Py 3.12+ on AWS Lambda

Arpit Bhayani

Arpit Bhayani

Dec 02, 2025 • 1 min read


Py 3.11 is more performant than Py 3.12+ on AWS Lambda!

And if you go by the benchmarks, then you should never run Node.js :) But of course, that considers only performance numbers and not familiarity.

By the way, this comes from a great article by Chris, where he benchmarked AWS serverless runtimes on light, CPU-intensive, memory-intensive, and I/O-heavy workloads, and even measured cold starts.

Some pretty interesting numbers. Give it a read.

Arpit Bhayani

Principal Engineer II at Razorpay - building Agent Studio, Ex-staff engg at GCP Memorystore & Dataproc, Creator of DiceDB, ex-Amazon Fast Data, ex-Director of Engg. SRE and Data Engineering at Unacademy. I spark engineering curiosity through my no-fluff engineering videos on YouTube and my courses