ProductionHigh concurrency
High-Availability Result Portal
Govt college portal serving 10,000+ concurrent students at result time.
Lead Engineer
Community & EdTechEnterprise & ERPNginxRedisPostgreSQLNext.js
Context
Problem & context
- Result day traffic spikes caused downtime and re-renders.
- Needed deterministic performance for 10k+ concurrent connections.
Architecture
Architecture & stack
- Nginx load balancer distributing traffic across multiple Node/Next instances.
- Redis caching of result payloads with cache warming jobs.
- PostgreSQL tuned with covering indexes for result queries.
Features
Key flows
- Pre-generated result pages cached before announcement.
- Bulk CSV ingestion with validation and rollback on failure.
- Progressive reveal of results with strict access control.
Challenges
Engineering challenges & solutions
- Avoiding thundering herd during announcement.
- Ensuring cache invalidation when corrections occur.
- Monitoring queues to stay within SLA during ingestion.
Impact
Impact & metrics
- Zero downtime during result declaration.
- Served 10k+ concurrent users with predictable latency.
- Reduced ingestion errors with streaming validators.
Next
What I’d improve next
- Add synthetic load tests per release.
- Ship offline PDF certificates for redundancy.