Stabilizing Infrastructure for 10x User Growth
How we migrated a crashing monolithic app to a scalable microservices architecture to handle viral growth.
01The Challenge
A consumer app experienced viral growth, jumping from 10k to 100k daily active users in weeks. Their monolithic MVP, hosted on a single server, began crashing repeatedly under the load. Database connections were maxing out, and latency was skyrocketing, threatening to kill their momentum.
- Frequent Downtime during peaks
- Single Point of Failure
02The Strategy
We executed a "Strangler Fig" migration pattern. We didn't rewrite everything at once. Instead, we peeled off the most resource-intensive features (like notifications and feed generation) into separate microservices, while keeping the core monolith running for basic CRUD operations.
Key Interventions
Containerization
Dockerized the application and orchestrated it with Kubernetes (EKS) for auto-scaling.
Database Optimization
Implemented read replicas and Redis caching to offload 80% of database traffic.
Load Balancing
Set up an Application Load Balancer to distribute traffic evenly across instances.
03The Results
The new architecture handled the traffic spike effortlessly. The app maintained 99.99% uptime during their biggest marketing campaign ever. Additionally, by optimizing resource usage, we actually reduced their monthly cloud bill by 40%.