Available to hire
I’m a Senior Software Engineer with over 10 years of experience delivering cloud-native platforms across FinTech, eCommerce, SaaS, and Healthcare. I specialize in Node.js (NestJS) microservices and React/Next.js SPAs, and I’ve consistently pushed reliability beyond 99.95% while driving cost savings. I’m passionate about shipping AI/RAG experiences that reduce MTTR, improve product growth, and mentoring engineers to build robust, scalable systems.
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Intermediate
Language
English
Fluent
Work Experience
Senior Full Stack Engineer at Peritus Inc
September 1, 2020 - November 3, 2025Led a greenfield marketplace using Python (FastAPI) with AI-driven recommendations; improved p95 latency and sustained 99.95%+ uptime through async optimization and performance budgets. Introduced GraphQL gateway and React Query caching, reducing frontend network calls by 34% and improving time to interactive. Built payments, invoices, and subscriptions with idempotent APIs, reducing charge errors by 41% and lowering customer support tickets. Delivered AI/RAG knowledge search behind secure endpoints; mean time to resolution decreased by ~31%. Implemented OAuth2/JWT with scoped RBAC; external audit passed with 0 high-severity findings. Set up GitHub Actions pipelines with Testcontainers; deployment frequency moved to daily with 97% success. Added OpenTelemetry traces and Grafana/Datadog dashboards; MTTD decreased 55% and MTTR 40%. Optimized Core Web Vitals through code-splitting and image CDN; LCP improved 23% and CLS stabilized. Established API standards (timeouts, pagination, error en
Full Stack Developer at Make IT Happen
June 1, 2020 - June 1, 2020Deployed Python (FastAPI) microservices on Azure App Service with CI/CD pipelines; optimized autoscaling and caching, improving response latency by 28% and cutting cloud spend ~20% through resource tuning. Modernized customer portal to React with SSR where needed; LCP improved 18% and key funnels conversion rose. Built REST/GraphQL services in Spring Boot/NestJS with Redis caching; p95 on hot endpoints dropped 27%. Implemented Kafka event streams and outbox pattern; duplicate processing fell below 0.1%. Launched admin suite in Angular with NgRx; time-to-dashboard decreased 35% and data errors fell. Embedded CI in Jenkins/GitHub Actions; change failure rate reduced from 15% to 7%. Added OpenTelemetry/Prometheus metrics; triage speed improved and SLOs reliably met. Wrote contract tests and Testcontainers setups; integration escapes reduced 33%. Built partner-sync adapters in Python (FastAPI); throughput doubled with typed clients and structured retries. Broke out invoicing into a .NET (C
Full Stack Developer at Make IT Happen
April 1, 2017 - June 1, 2020Built NestJS services and React admin portals; p95 improved 30% and uptime held at 99.9% across three consecutive quarters. Deployed Kafka + CDC for near-real-time sync; data freshness moved from minutes to seconds and reprocessing time dropped 56%. Launched a customer-facing AI/RAG FAQ; ticket deflection improved 23% and satisfaction scores increased 8 points. Implemented OAuth2/JWT with key rotation and scope-based access; 100% of token replay attempts blocked in red-team tests. Established GitHub Actions CI with contract tests; change failure rate decreased from 15% to 7% within two quarters. Migrated key flows to React with accessibility and performance upgrades; LCP improved by 18% and conversion rose 6% on targeted funnels. Ran incident post-mortems and SLO tracking; major incidents per quarter dropped from 6 to 3.
Back End Developer at Avensys Consulting
June 1, 2015 - June 1, 2015Built high-throughput APIs in Java/Spring Boot and Python/Django, FastAPI; write throughput increased 2.1x and p95 query latency decreased 24% with PostgreSQL tuning. Introduced Redis caching and rate limits; 5xx spikes during peak hours fell 36%. Automated CI/CD with Jenkins and Terraform; release time reduced 65%. Instrumented Grafana/Prometheus dashboards; MTTD down 43%, MTTR down 31%. Collaborated with UI teams on API contracts; breaking changes reduced 30% and partner satisfaction improved. Delivered finance reporting jobs in .NET (C#) with SLAs; on-time completion 99.9%. Built a lightweight ops console in Angular to manage flags/rules; moved on-call toggles from SSH to UI. Deployed services on AWS and GCP; unified IaC modules for repeatable rollouts. Hardened PostgreSQL with streaming replicas + PITR; recovery drills met RTO < 10 min.
Back End Developer at Avensys Consulting
August 1, 2011 - June 1, 2015Developed high-throughput APIs in Node.js with PostgreSQL tuning; write throughput increased 2.2× and p95 query latency decreased 27%. Designed Redis caching and rate-limiting; revenue-impacting 5xx during peak hours fell by 39%. Automated CI/CD with Jenkins and Terraform; release time reduced by 68% and environment parity significantly improved. Instrumented Prometheus/Grafana dashboards with SLO-based alerts; MTTD down 43% and MTTR down 31%. Introduced API versioning and consumer-driven contracts; breaking changes in downstream systems reduced by 38%.
Education
Bachelor's Degree in Computer Science at Nanyang Technological University, Singapore
August 1, 2011 - June 1, 2015Bachelor's Degree in Computer Science at Nanyang Technological University, Singapore
August 1, 2011 - June 1, 2015Bachelor's Degree in Computer Science at Nanyang Technological University, Singapore
August 1, 2011 - June 1, 2015Qualifications
Industry Experience
Financial Services, Healthcare, Software & Internet, Retail, Professional Services
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Intermediate
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