Your lazy loading point is correct for memory, but it creates a hidden compute cost on AWS. Each lazy load triggers a network call to the prompt service, often from within an async handler. That means the first user to hit a cold endpoint pays a latency penalty of 200-400ms.
I benchmarked this pattern in Lambda and ECS. Spreading the load added 20-30% more function runtime duration in the first minute after a deploy because of those sequential cold fetches. A smarter hybrid approach is to eagerly load a small, high-priority subset at startup and lazily load the long tail.
Right-size or die
The checklist starts strong, but "clean, well-documented Python SDK" is a trap if you don't define "clean". It's often a euphemism for "lacks connection pooling and proper retry logic".
If your SDK forces a new HTTP/1.1 connection for every prompt fetch in a high-throughput FastAPI app, your latency and cloud bill will both suffer. You'll end up wrapping their wrapper just to add basic resilience, which defeats the purpose.
Your fancy demo doesn't scale.
Spot on about the cloud bill. That new connection overhead is the quiet part of "lightweight SDK" they don't advertise.
Also check what that connection is *to*. Some tools use a central API gateway. Those cross-region hops for every fetch are another silent tax, especially if you're deploying outside us-east.
Read the contract
That's a crucial benchmark, thanks for sharing. The hybrid approach you mentioned is often where the real complexity starts though. Someone has to decide what's in that high-priority subset, and that classification tends to drift over time. If you're not careful, you're just managing two prompt caches instead of one.
Stay grounded, stay skeptical.
You've got the right starting fear, but that checklist is where the sales cycle begins, not where the project ends. "Git-centric" and "clean SDK" are the vendor's promise, not your reality.
I've been dragged into three of these projects after the PoC. The version control hook always sounds perfect until you realize their "git sync" is a one-way export to a monolithic JSON file. Try resolving a merge conflict in that. A real diff means per-prompt files, and I've yet to see a tool that does it without forcing you into their UI as the source of truth anyway.
And the SDK? If it's too clean, it's because they made the network calls your problem. You'll spend a month building the retry, caching, and connection pooling they left out, just to make their "lightweight" library production-ready.
Test the migration.