AVAILABLE FOR NEW PROJECTS

Fullstack
Craftsmanship
at Scale

Bridging the gap between robust enterprise systems and bespoke freelance solutions. Expert in scalable architecture and high-performance web apps.

POWERING NEXT-GEN APPLICATIONS WITH

Elysia JS

Elysia.js

Elysia JS

Next.js

Elysia JS

PostgreSQL

Elysia JS

FastAPI

Elysia JS

Django

Elysia JS

Prisma ORM

Elysia JS

Express.js

Elysia JS

Bun

Dual Career Path

Balancing corporate rigor with freelance agility.

Corporate Experience

Fullstack Engineer

2023 - Present

Wilmar Consultancy Services - Indonesia

Engineered feature-flag runtime configuration, microservices with Node.js and REST APIs, AWS S3 storage, Azure Pipelines CI/CD, and SAP RFC→IDoc integrations to support 1,000+ enterprise users while improving API performance by 25% and cutting release overhead by 35%.

Fullstack Engineer

2022 - 2023

Umify Pte, Ltd. - Singapore (Remote)

Optimized MVP performance using Next.js (TypeScript), PostgreSQL, and Prisma, integrating Stripe payments, SendGrid email automation, and Google OAuth 2.0 in an Agile environment to achieve biweekly releases with <2% post-deploy issues and +20% user satisfaction.

Software Engineer Intern

2022

Umify Pte, Ltd. - Singapore (Remote)

Built and launched the MVP with Next.js, TypeScript, and PostgreSQL, migrating from React.js and Express.js to reduce page load time by 40% while delivering features through Agile sprints.

Web Developer

2022 - 2023

Collaboration For Good, Inc - USA

Developed responsive web platforms with HTML, Tailwind CSS, and JavaScript and optimized ExpressionEngine CMS performance to boost user engagement by 35% and site speed by 50%.

IT Assistant

2021 - 2022

McBurney Disability Resource Center - USA

Managed 10,000+ assets using Cloud ERP tools and barcode scanning, and supported accessible content creation with Haskell Pandoc and Git/GitBash to improve inventory efficiency by 40% and maintain 99.9% data accuracy.

Freelance Studio

Tenant Management System

Ongoing

Cherry / Sky Kost

Built a property management system to streamline landlord–tenant relationships by centralizing tenant records, lease details, and payment tracking, featuring a tenant portal, admin portal, and integrated bookkeeping tools that help landlords efficiently manage properties, finances, and tenant interactions in one platform.

Shipping Management System

Ongoing

PT. Mitra Laju Interocean

Developed a role-based shipment and costing tracking system that enables teams to monitor logistics, expenses, and operational data in real time, with controlled feature access per user role to ensure security, clarity of responsibilities, and streamlined workflows across departments.

Booking Management System

Delivered

Quantum Sports

A padel court booking system is a web app that lets clients book courts and coaches with online payments, while an admin dashboard manages court and coach schedules, assists customer bookings, and provides bookkeeping features to track financials and transactions in one centralized system.

Promotional Page (CMS)

Delivered

Chez Bakery

Built a promotional page to showcase the bakery and its products, and developed a custom CMS that enables the business to easily manage, update, and publish their bakery content, product listings, and promotional information without needing technical support.

Promotional Page

Delivered

PT. Tujuh Anugrah Abadi

Developing a high-converting landing page for printing solutions designed to boost sales and enhance customer engagement. The page features intuitive product search, streamlined browsing, and a user-friendly layout that makes it easy for customers to find the right printing products and services quickly, improving the overall shopping experience and driving higher conversions.

Featured Work

Selected projects from corporate and freelance tracks.

How I Can Help

Specialized services tailored for scaling startup and enterprise modernization.

Web Application

Full-cycle development of responsive, accessible, and performant web apps using the React ecosystem.

API Architecture

Designing and building type-safe, documented, and scalable REST APIs using the Node Framework.

Tech Consulting

Helping businesses choose the right architecture, optimize performance, and turn complex technical challenges into scalable, efficient digital solutions.

Let's Build
Something
Extraordinary

Currently accepting new freelance projects and open to discussing engineering roles. Let's turn your vision into shipped code.

winstencoellins13@gmail.com

Medan, Indonesia (Remote Friendly)