architecture

A lab design review still had a cron server for a nightly job. Classic Lambda had already stopped at 900 seconds. Name the primitive, or name the stop-rule that keeps the box.

On 9 Sep 2026 AWS raised LMI async and ESM timeout from 15 to 90 minutes (5,400 s). A 90-minute SQS consumer needs at least 9 hours of visibility. Sync and classic on-demand Lambda stay at 15 minutes.

On July 23, 2026 AWS GA’d the Durable Execution SDK for .NET (Amazon.Lambda.DurableExecution). Score your C# workflows against our durable-vs-Step-Functions matrix — most integration-heavy flows still belong in ASL.

After Cognito multi-Region replication (June 2026), a B2B API platform (~18k RPS peak) cut auth-related 5xx during a regional drill from 4.2% → 0.1% — but a missing WAF rate rule still let a scraper burn $1.8k in a weekend.

For an on-prem MySQL estate (~1.1 TB, 340 tables), DMS full load + CDC into Aurora MySQL cut planned downtime from 6h → 18 min — LOB misconfiguration added 11 hours of rework before cutover.

For a mid-market retailer (~2.4M SKUs, checkout p95 1.9s → 420ms), DynamoDB cart + Step Functions checkout + conditional inventory cuts held 2.1k checkout RPS — after a cache-as-inventory mistake oversold 380 units in 12 minutes.

For a retailer DW exit (~42 TB logical, 18 nightly Glue jobs), Aurora→Redshift zero-ETL retired 11 jobs and cut dashboard freshness from 6h → ~15 min — concurrency scaling on zero-ETL (March 2026) absorbed Monday open spikes.

For a .NET monolith (~220 endpoints, ~$28k/mo EC2), strangling 14 endpoints to Lambda cut p95 on those routes 1.4s → 210ms — an early LMI move on spiky traffic wasted ~$3.2k in idle capacity provider hours.

For a multi-district LMS (~52k concurrent exam submissions in 30 min), SQS decouple + Aurora Serverless v2 held p95 submit at 410 ms — off-peak monthly compute −71% vs always-on EC2.

For a card-acquiring fintech (~12M authorizations/mo), Payment Cryptography + PCI-scoped account cut HSM rack lease −$18k/mo — fraud review queue p95 2.4s → 380ms after EventBridge Pipes idempotency fix.

For an enterprise lake (~38 TB Iceberg, 8.4k small files), S3 Tables managed compaction cut Athena scan spend −35% — compaction OPEX −90% vs pre–July 2025 pricing on the same workload.

SES Global Endpoints (Dec 2024) add $0.03/1k for active-active failover across two regions. MREP decision matrix, replication rules, Tenant Management, and a reproducible readiness benchmark — for architects choosing regional vs multi-region email.