William Justin
Fullstack Engineer
// Tech Stack
// My Work
Featured Projects
These are some of my favorite things I've built so far. Each one represents a challenge, a lesson, and a chance to turn ideas into products and something meaningful.
MCP Tool Schema Patcher
A Java and Kotlin library that repairs MCP input schema references and Kotlin nullability for Spring Boot 3.5 applications using Spring AI 1.1.x.
Duff Intelligence with MCP
An AI revenue intelligence copilot with MCP integrations that helps sports venue owners make smarter business decisions.
Extra Mile Valley: Interactive Learning Gamification
A web-based gamification platform designed to immerse employees in company values through interactive gameplay.
Forgr: Online Store Builder Platform
A direct selling platform that lets brands launch their own storefront, own their customers, and sell without marketplace commissions.
Patchmentation: A Python Library for Patch Augmentation
Patch augmentation is data augmentation technique that synthesizes training images by combining objects from multiple images into different backgrounds.
DeepFaceDrawing: Deep Generation of Face Images from Sketches
A complete implementation of DeepFaceDrawing with a two-stage training pipeline, CLI inference, Docker deployment, and a web interface.
Grayscale Face Image Colorization
A generative model that colorizes grayscale face images into realistic, full-color portraits.
FiftyOne Embeddings Visualization
An interactive dashboard for exploring computer vision embeddings and visually analyzing image similarity using FiftyOne and Plotly Dash.
Person Face Dataset
A dataset with 10K images of person face generated by thispersondoesnotexist.
Person Face Sketches Dataset
A dataset with 21K+ images pair of person face photos and sketches.
// Recognition
Awards & Honors
Recognition earned through consistent delivery at work and active contribution to the competitive programming community.
Rated Exceed Expectation in the 2025 performance cycle at Traveloka.
Consecutive quarterly recognition for sustained high performance and contributions at Samsung Research.
Recognized for exceptional performance and impact during Q1 2024 at Samsung Research.
Authored competitive programming problems for one of Asia's most prestigious ICPC regional contests.
Contributed original problems to the Indonesia National Contest, a premier national-level programming competition.
// Credentials
Certifications
Industry and institutional certifications that validate my technical expertise, engineering standards, and communication skills.
Professional certification validating expertise in designing complex AWS architectures.
Foundational certification validating cloud fluency and AWS core services knowledge.
Internal Samsung Research certification recognizing software engineering proficiency at a professional level.
Overall band score 7.5 / 9.0 — demonstrating proficient academic English across all four skills.
// Get In Touch
Have Something in Mind?
Whether you're building a startup, exploring AI, or looking for someone to help bring an idea to life, I'd love to hear your story.