INTRODUCTION

Fullstack Javascript Developer with 10+ years of experience building scalable web applications using React, Node.js, and cloud solutions (AWS, Azure). Passionate about optimizing system performance and enhancing user experience.

EXPERTISE

Core Skills

  • JavaScript / TypeScript
  • Node.js (NestJS, Express.js)
  • React.js, Next.js, Gatsby
  • Elasticsearch, Redis, SEO Optimization
  • Web Security & Performance Optimization

Additional Skills

  • Web Server: Nginx, Apache
  • CI/CD & Cloud Services: Azure DevOps, AWS, Jenkins, Cloudformation
  • Testing: Unit Testing (Jest, Mocha), End-to-End Testing (Cypress, Selenium)
  • Database & Caching: SQL, No-sql, CosmosDB
  • Web Server: Nginx, Apache

EXPERIENCE

April 2023 – Present

MODEC | DNA

Senior Software Engineer

Remote

- Revamped a 2-year-old internal search engine, improving document retrieval speed by 30%.

  • Fetching file changes from data hub by listening changes via API.
  • Number of workers are extensible via /healthcheck API and Azure Monitoring tools.
  • Doing OCR using Azure Cognitive service to define additional metadata/properties.
  • Flatten/Rotate PDF files/images for better experience.
  • Built a web application for viewing PDF files (using pdf.js) with highlight positioning.
  • Shared search query/results via hyperlink among team/project members.
  • Optimized rendering phase by pre-building the first page as image, rendering in parallel, pagination support, tags caching, and categories creation.
- Developing Sensei, an AI-powered assistant using GPT-4(o) & Retrieval-Augmented Generation (RAG), enhancing response accuracy by 40%.
  • Engineered a robust and scalable AI-powered chat system utilizing OpenAI’s Chat Completion APIs and Azure AI Search.
  • Implemented semantic and hybrid search capabilities for accurate responses.
  • OpenAI chat integration with real-time streaming of chat responses using Next.js framework.
  • Custom prompt engineering for specialized system and SME guides.
  • Contextual Document Retrieval with Cosmos DB.
  • Chat history management, limiting up to 30 messages with file content as part of the query.
  • User identification and privacy through hashed IDs (userHashedId).
  • API development with OpenAIStream function for efficient data flow.
  • Secure/scalable configuration via Azure Key Vault and Environment Variables.
  • Scalable Architecture Design by modularizing services for each mode.

Technologies used:
- TypeScript, Next.js
- Azure Cognitive Search, Cosmos DB, Azure OpenAI
- Langchain, Langfuse (self-hosted)

Dec 2019 – Mar 2023

EDUBAO | EDUBAO.ORG

Software Engineer

Ho Chi Minh City, Vietnam

As the first developer of Edubao Viet Nam, I was in charge of setting up and building edubao.org and its ecosystem to introduce our insurance packages for students/workers aiming to study/work in Germany. Key contributions include:

  • Built edubao.org, a study & insurance portal for students in Germany.
  • Developed a dynamic blog system with Squidex.io CMS, SEO support, and user-friendly interfaces for marketing/business teams.
  • Integrated Google Tag Manager to track user behavior, increasing conversion rates.
  • Led the migration from Azure to AWS (Lightsail, EC2, S3, Cloudfront).

Tech stack: ReactJS, Gatsby, Next.js, GraphQL, Elasticsearch, AWS, Azure DevOps.

June 2017 – Dec 2019

8BIT ROCKSTARS | NFQ.ASIA

Web Developer

Ho Chi Minh City, Vietnam

- Core developer for Heidelpay, a German payment gateway.

  • Designed a dynamic financial dashboard with Chart.js, tracking revenue in real-time.
  • Set up the frontend's foundation utilizing ReactJS.
  • Implemented dynamic dashboard/widgets with Chart.js.
  • Tracked revenue via transaction type/grouped as orders.
  • Implemented dynamic filtering via query string.
  • Learned PHP and techniques to build a worker handling ~200 transactions per second by breaking down into smaller states from the workflow.

Technologies used:
- PHP (Symfony 3), MySQL 5.7, ReactJS (old lifecycle, not hooks)
- Git/GitHub (Pull Request flow), PostgreSQL, Mongo, RethinkDB, Redis, RabbitMQ.

July 2015 – June 2017

TRIPOLIS SOLUTIONS

Fullstack Developer

Vietnam

Developed a Drag and drop campaign management system (Email marketing).

  • Maintained the frontend using AngularJS to build access portal, handle authentication/authorization, and redirect to main web-based applications.
  • Learned React.js (2015) and built component-based architecture to speed up complex drag & drop nodes for marketing campaign creation.
  • Migrated AngularJS code to ReactJS incrementally.
  • Used Ruby to build an individual authentication service (middleware).
  • Utilized Go to handle heavy tasks supporting high concurrency as internal services.

Technologies used:
- PHP (Symfony 3), MySQL 5.7, ReactJS (old lifecycle, not hooks)
- Git/GitHub (Pull Request flow), PostgreSQL, Mongo, RethinkDB, Redis, RabbitMQ.

Sep 2014 – June 2015

LUDIINO CO., LTD

Front-end Developer

Ho Chi Minh City, Vietnam

- Developed Golfconnect24, a cloud-based golf management platform.

  • Built a real-time booking & e-scorecard system using AngularJS.

Apr 2014 – Sep 2014

Eztek Software Development Co., Ltd

Internship

Ho Chi Minh City, Vietnam

Project: Car Finding E-Commerce System (April – June 2014)

PERSONAL PROJECTS

AI Researching

Example to show off abilities of document intelligence and ChatGPT using to extract data from given PDF/image files.
GitHub: https://github.com/211211/extract-data-from-pdf-or-image-with-document-intelligence-and-chatgpt

Edubao Sample Test - Interview

To learn new state management library called MobX
GitHub: https://github.com/211211/edubao-sample-test/blob/master/

Extracting image from video - Interview

To use ffmpeg to extract an image at a given timestamp for a given video
GitHub: https://github.com/211211/extract-image-repo/tree/main

EDUCATION

CONTACT & LINKS