Hen Heang

Backend / AX Software Engineer

Java · Spring Boot · MyBatis · PostgreSQL · Oracle · AI-Assisted Development

Seoul, South Koreahenheang15@gmail.com LinkedIn GitHub Portfolio

Professional Summary

Backend / AX Software Engineer with 2+ years of experience building Java and Spring Boot applications in Cambodian and Korean enterprise environments. Experienced in REST APIs, MyBatis, Spring Security, PostgreSQL, Oracle, and SQL-driven business logic for financial and B2B platforms. I have integrated practical LLM-powered product features and use Claude Code and Codex for AI-assisted planning, analysis, implementation, review, testing, and documentation. I am learning Agent Harness, MCP, guardrail, evaluation, and observability concepts through structured practice; these are growth areas, not claims of production-scale agent infrastructure experience.

Professional Experience

Bizplay

October 2025 – Present

Backend Developer (Java & Spring Boot)· Seoul, South Korea

Implement Java and MyBatis services and SQL queries against an Oracle database for government-facing financial systems.
Build supporting frontend pages with HTML, CSS, and JavaScript (jQuery) for internal enterprise tools.
Maintain and improve the stability of enterprise web applications in a Korean enterprise environment.
Collaborate with cross-functional teams following Korean enterprise development conventions.

JavaMyBatisOracleJavaScriptjQueryHTML/CSS

KOSIGN (Korea Software Innovation Global Network)

January 2024 – October 2025

Software Engineer· Phnom Penh, Cambodia

Designed and developed REST APIs with Spring Boot and MyBatis for an enterprise B2B billing platform integrated with Vietnamese banking systems.
Designed PostgreSQL schemas and optimized query performance for high-volume transactions.
Implemented Spring Security with JWT authentication to secure enterprise-grade APIs.
Integrated Zalo, SMS, and Telegram delivery channels for transactional notifications.
Collaborated daily with Korean development teams on architecture design and code reviews.

Java 8+Spring BootSpring SecurityPostgreSQLMyBatisNext.jsTypeScript

Selected Projects

H-Phsar

Backend API

Code Case Study

Backend API for a B2B marketplace connecting distributors and retailers, built on Spring Boot 3 and PostgreSQL.

Designed the data model for stores, product catalogs, and carts, and implemented an order state machine with OTP-based verification.
Delivered real-time order notifications over WebSocket.

Spring Boot 3Java 17MyBatisPostgreSQLWebSocket

Money Flow

Backend API

Code Live Case Study

Personal finance API and PWA on Supabase Postgres with row-level security, backed up daily to Neon.

Implemented budgeting, savings-goal, and recurring-transaction logic behind Postgres row-level security.
Added an AI chat endpoint over Google Gemini for spending insights and web-push budget alerts.

Next.jsTypeScriptSupabaseGoogle GeminiWeb Push

Hengo

Full-Stack App

Code Live Case Study

AI-powered workplace Korean and growth platform on Next.js, Supabase Auth/Postgres with RLS, and JWT-verified AI routes.

Built Today’s Mission, spaced-repetition learning, interview preparation, and progress tracking in one workspace.
Kept data behind Supabase RLS and routed authenticated AI work through thin Next.js handlers.

Next.js 16TypeScriptSupabaseVercel AI SDKOpenAI

Technical Skills

Backend

JavaSpring BootMyBatisSpring SecurityREST APIsMaven

Database

PostgreSQLOracleMySQLSQL OptimizationSchema Design

AI & Developer Productivity

Claude CodeCodexGoogle Gemini APIOpenAI APILLM IntegrationPrompt DesignAI-Assisted Code Review

Frontend

Next.jsReactTypeScriptJavaScriptjQueryTailwind CSS

Tools & Delivery

GitGitHubIntelliJ IDEAWebStormPostmanSwaggerVercelRailway

Education

March 2020 – May 2024

Royal University of Phnom Penh

Bachelor of Computer Science

Focused on software development, algorithms, and web technologies.

July 2023 – April 2024

Korea Software HRD Center

Full-Stack & Mobile Development Training

Intensive training in full-stack development and Android application development using Java and Kotlin.

March 2021 – July 2021

ANT Technology Training Center

Basic C++ Programming Certificate

Introduction to programming concepts and problem solving with C++.

Languages

KhmerNative

EnglishProfessional working proficiency

KoreanElementary conversational