← Back to Insights

Lessons Learned

36 engineering war stories and lessons learned.

Collected from our engineers and the wider industry, these 36 stories cover Redis meltdowns, microservices regrets, cloud cost surprises, and Kubernetes failures — and what each one teaches.

Redis Cache Overload Kills Database

Redis noeviction: When Writes Stop

Stale Cache Data Disaster

Cache Invalidation: Two Hard Lessons

Multi-Layer Caching Failure

Rate Limiter Redis Crash

Session Storage Redis Migration

Spot Instance Black Friday Disaster

The $50,000 CloudWatch Logging Bill

Multi-Region Replication Nobody Used

Staging Costs More Than Production

VPC Egress Charges Surprise

Autoscaling That Killed the Database

Health Checks That Lied

ConfigMap Typo Outage

Docker Image With 47 CVEs

High Availability That Wasn't

Cross-AZ Traffic Bill Shock

Pod Eviction Cascade

Ingress Controller Single Point of Failure

Microservices #21

Microservices for the Wrong Reasons

Microservices #22

Consolidating Microservices Gone Wrong

Microservices #23

Scaling Everything Except the Database

Microservices #24

20,000 Workloads to Kubernetes: Post-Mortem

Microservices #25

Splitting the Monolith Too Fast

Microservices #26

Partial Failure Hell

Microservices #27

1K to 10K RPS Complexity Explosion

Microservices #28

Microservices Were Organizational

Architecture #29

Blue-Green Config Drift

Architecture #30

Lambda Cold Starts: Fixing Our P99

Architecture #31

Service Mesh Overhead: What We Got Wrong

Architecture #32

Serverless Lock-In Reality

Architecture #33

Blue-Green Database Nightmare

Architecture #34

Cache That Added Latency

Architecture #35

Event Sourcing for CRUD

Architecture #36

Horizontal Scaling Bottleneck