Case Study: B2B SaaS Infrastructure Rebuild on AWS
A fast-growing B2B SaaS startup rebuilt its AWS architecture with auto-scaling and incident response — eliminating outages and cutting infrastructure cost 25%.
Client: B2B SaaS Startup — B2B SaaS / Technology
The challenge
- Weekly outages as customer load grew
- No auto-scaling, monitoring, or incident response process
- Infrastructure costs growing faster than revenue
- Engineering team firefighting instead of shipping
The approach
- Architecture review: Mapped current AWS footprint, single points of failure, and cost drivers.
- Target design: Designed an auto-scaling, multi-AZ architecture with proper observability.
- Phased migration: Re-platformed services one at a time with zero-downtime cutovers.
- Observability and alerting: Implemented CloudWatch + Datadog + PagerDuty with on-call rotation.
- Incident response playbooks: Wrote and rehearsed playbooks for the top 5 failure modes.
Results
- Zero unplanned outages in the following 6 months
- Infrastructure costs reduced 25%
- Engineering velocity (deploys per week) up 30%
- Mean time to recovery (MTTR) under 15 minutes
Tools used: AWS, Terraform, Datadog, PagerDuty, GitHub Actions, CloudWatch