Financial Services
Multi-Rail Payment Platform
The Challenge
A rapidly scaling payments startup needed to support fiat, ACH, and crypto payment rails simultaneously. Their legacy monolithic payment handler couldn't process concurrent multi-rail transactions, causing reconciliation errors and blocking product expansion into crypto-native markets. Compliance reporting was manual and error-prone.
What We Built
Designed an event-driven microservices architecture using NestJS and Kafka, with a shared ledger abstraction layer that unified transaction state across Stripe (card/fiat), ACH via Nacha-compliant provider, and stablecoin settlement on Ethereum and Polygon. Each rail runs as an isolated service with idempotent handlers and dead-letter queues for failure recovery. Deployed on Kubernetes (AWS EKS) with full Prometheus/Grafana observability stack. Automated compliance reports generated from event stream.
NestJS
Kafka
PostgreSQL
Stripe
Kubernetes
AWS EKS
Prometheus
Outcome
Card, ACH and stablecoin payments live on one shared ledger, with every transaction reconciled from the event stream.
Enterprise
High-Throughput API Migration
The Challenge
A B2B SaaS company's monolithic Java application was hitting hard throughput ceilings during market-hours load. Peak traffic caused cascading timeouts, and the database was a shared bottleneck. Engineering velocity had dropped to near zero because any change risked destabilizing the entire system.
What We Built
Used strangler-fig pattern to incrementally decompose the monolith into NestJS microservices, with Kafka as the event bus and Redis for distributed caching. Zero-downtime migration using shadow traffic and feature flags. Rebuilt CI/CD pipeline with GitHub Actions, automated contract testing between services, and progressive delivery via ArgoCD. Established SLOs and alerting with Prometheus and Grafana.
NestJS
Java
Kafka
Redis
PostgreSQL
Kubernetes
GitHub Actions
ArgoCD
Prometheus
Outcome
Migrated with zero downtime. Peak market-hours load handled without timeouts, and the team shipping changes safely again.
Blockchain
Real Asset Tokenization Platform
The Challenge
A real estate investment firm wanted to fractionalize commercial property ownership and enable secondary trading. Existing approaches required manual cap table updates, had no on-chain compliance enforcement, and couldn't support investor KYC requirements within the token transfer mechanism itself.
What We Built
Designed an ERC-1400 compliant security token architecture on Polygon. Built a permissioned token with on-chain transfer restriction modules enforcing KYC status, investor accreditation, and jurisdiction rules — validated via a Chainlink-oracle-connected compliance registry. Built an investor portal (NestJS backend) with Jumio KYC integration, cap table management, and dividend distribution tooling. Test suite covering every transfer rule. Prepared for Quill Audits third-party security review.
Solidity
Polygon
ERC-1400
Chainlink
NestJS
PostgreSQL
Jumio
Outcome
Delivered ahead of the initial estimate and audit-ready at launch, with tokenized property live on the platform.
