Jeff Kwong, Developer in Las Vegas, NV, United States
Jeff is currently unavailable

Jeff Kwong

Bio

Jeff is a senior back-end engineer with 8+ years of experience building scalable, cloud-native services at Capital One, Amazon, Microsoft, and MGM Resorts. He specializes in Python-based microservices and distributed systems, with hands-on experience in Go, DynamoDB, Kafka-style event flows, and AWS. Jeff delivers high-performance, low-latency platforms with a strong focus on reliability, observability, and operational excellence.

Portfolio

Capital One Financial
Java, Amazon Web Services (AWS), Jenkins, GitHub Actions

Experience

  • Java - 7 years
  • Python - 7 years
  • GitHub - 7 years
  • Spring Boot - 6 years
  • Node.js - 5 years
  • AWS Command Line Interface (CLI) - 5 years
  • JavaScript - 5 years
  • Go - 4 years

Preferred Environment

Visual Studio Code (VS Code), GitHub, Docker, PostgreSQL, Python, Java, Spring Boot, Slack, Amazon Web Services (AWS)

The most amazing...

...things I've built and operated are large-scale, low-latency back-end services with strict reliability guarantees, meeting sub-25ms SLAs at enterprise scale.

Work Experience

Senior Software Engineer

2024 - 2026
Capital One Financial
  • Led the architecture and delivery of a high-throughput, distributed back-end platform, partnering across engineering, legal, and compliance.
  • Designed event-driven ingestion and CDC pipelines feeding S3 and downstream consumers, emphasizing idempotency, resiliency, and observability.
  • Led the development of a Vue and Node.js micro-front end for 5,000+ call center agents.
Technologies: Java, Amazon Web Services (AWS), Jenkins, GitHub Actions

Experience

Payments Tokenization and Verification Service

I developed a PCI-aware tokenization and verification service that securely integrates with third-party payment processors, replacing sensitive card data with internal tokens. The service exposes tokenize and detokenize APIs, enabling downstream systems to operate without direct access to raw payment data.

I implemented strict security boundaries, audit logging, and role-based access controls, while ensuring high availability and supporting zero-downtime migrations through feature flag routing.

This project reflects real-world payment platform practices and demonstrates my experience with financial systems, security-first design, and enterprise-grade service ownership.

Skills

Libraries/APIs

Flask API, Vue, Node.js, React, REST APIs, OpenAI API

Tools

GitHub, AWS Command Line Interface (CLI), Jenkins, Pytest, Git, Terraform, Slack

Languages

Python, Java, C++, JavaScript, C#, TypeScript, SQL, Kotlin, Go, C#.NET, GraphQL, CSS

Frameworks

Spring Boot, Express.js, .NET, Django, ASP.NET Core, Tailwind CSS

Paradigms

Agile Software Development, Azure DevOps, Microservices, Microservices Architecture, Database Design, REST

Platforms

Visual Studio Code (VS Code), Amazon Web Services (AWS), Docker, Azure, Azure Service Fabric

Storage

PostgreSQL, Amazon DynamoDB, Cassandra, MySQL, Azure Cosmos DB, MongoDB, Amazon S3 (AWS S3)

Other

GitHub Actions, API Integration, Vite, APIs, eCommerce, Card Payments, Architecture, Full-stack, Web Development, CI/CD Pipelines, Payment Gateways, Full-stack Development, Large Language Models (LLMs), AI-generated Code, Gemini, Vibe Coding, Authentication, Back-end, Database Optimization, Third-party APIs, Software Architecture, Artificial Intelligence (AI), FastAPI, CDC, OpenTelemetry

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