Case studies
The underlying products are private, so I cannot publish their repositories. I can show the problem, my responsibilities, the tradeoffs we made, and the result without exposing customer or company data.
Financial backend systems with KYC/AML, exchange integrations, blockchain nodes, and polyglot persistence.
Enabled compliant onboarding and scalable backend features for financial workflows.
Role: Backend developer for financial platform services
Scope: KYC/AML, document validation, Binance integration, PostgreSQL, MongoDB, Neo4j, Redis, Elasticsearch
Decision: Used the right persistence model for each workflow instead of forcing one database pattern.
What could go wrong: Sensitive document handling and correctness in financial/accounting flows.
Scaling a production NestJS backend with PostgreSQL, Redis, RabbitMQ, Prisma, and disciplined team delivery.
Maintained 99.9% uptime, reduced API latency by 40%, and supported consistent delivery with a backend team of 8 engineers.
Role: Engineering Manager / backend architecture owner
Scope: NestJS modules, Prisma repositories, PostgreSQL, Redis, RabbitMQ, Nginx, delivery process
Decision: Improved performance and maintainability without rewriting stable business behavior.
What could go wrong: Production regressions on high-traffic workflows.
Gold and crypto trading backend systems with live pricing, chart history, wallets, payments, and provider/admin operations.
Shipped trading and payment backend capability for gold and crypto market flows, including live pricing, chart history, wallet transactions, gateway integrations, and production operations.
Role: Freelance backend developer for trading and payment systems
Scope: Gold/tether/melted-gold orders, live pricing, chart history, wallets, crypto gateways, provider/admin operations
Decision: Kept live market flows responsive while preserving durable wallet, transaction, and payment records.
What could go wrong: Financial correctness, gateway reliability, market-data freshness, and secure provider/admin workflows.
A consulting platform with chat, VoIP, video, learning modules, and backend microservices.
Supported 500+ concurrent users with real-time communication flows and faster SQL retrieval paths.
Role: Backend developer on communication-heavy platform
Scope: Chat, VoIP, video sessions, SQL optimization, RabbitMQ, Angular integration
Decision: Separated communication orchestration from persistence while keeping latency-sensitive paths direct.
What could go wrong: Call reliability, session state synchronization, and database bottlenecks.