You add a sixth Lambda trigger to your OrderEvents table, deploy it, and within 20 minutes your SLA dashboard goes red. Latency on order writes jumps from 4ms to 40ms. The function itself is fine. The table is fine. The problem is that five other Lambdas are already hitting the same partition key on every write, and you just made it six. DynamoDB's internal partition throttling doesn't care that each function looks clean in isolation.
This is an N+1 trigger problem, and your AI coding assistant cannot catch it. Not because it lacks intelligence, but because the fact that five Lambdas already target that table lives in your AWS account and your full codebase — not in the file your assistant has open.
Infrawise · npm
Why the LLM Can't See the Pattern
When you ask Claude to write a new order processing Lambda, it reads the file you have open and generates code that looks correct — because in the context of that one file, it is correct. It doesn't know about ProcessRefundsLambda, NotifyFulfillmentLambda, SyncInventoryLambda, UpdateAnalyticsLambda, and AuditTrailLambda, all of which you wrote in previous sprints and which all write to the Orders table.
