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Sim Hann Zern

Hands-on Lead Developer with a track record of building and shipping complex, full-stack systems from the ground up. I specialize in bridging high-performance mobile apps with scalable backend architectures, having involved everything from Golang-driven microservices and RPC/API integrations to custom Laravel backends capable of handling complex MLM hierarchical data. Whether it’s salvaging a failed marketplace project for a 3-month launch or engineering Web3 ecosystems with Geth and automated smart contract payouts, I focus on writing the core libraries and CI/CD pipelines that help teams move faster. I'm a fast-paced builder who prefers to lead from the code, mentoring juniors by tackling technical debt and refactoring alongside them.

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Skills

  • VueJs
  • NuxtJs
  • TypeScript
  • Flutter
  • Fastlane
  • Node.js
  • NestJS
  • Go
  • MongoDB
  • Capacitor
  • Docker

Integrations

  • Stripe
  • eGHLeGHL
  • iPay88iPay88
  • VeriffVeriff
  • AWS KMS
  • Firebase
  • Meta Pixel
  • Sentry

Languages

  • EnglishWritten: NativeSpoken: Native
  • Mandarin ChineseWritten: ProfessionalSpoken: Professional
  • MalayWritten: ConversationalSpoken: Conversational

Featured Projects

Pay It ForwardFeatured

Pay It Forward (PIF) is a meal-sharing platform where individuals and businesses can support community meals for those in need. Because sharing is caring, our trusted food support platform connects donors with verified local partners, ensuring every contribution makes a real difference.

Shipped

Hope MissionFeatured

Hope Mission is a non-profit organization dedicated to providing essential support and resources to underprivileged communities. Through various initiatives, they aim to improve the quality of life for those in need, focusing on education, healthcare, and community development. This project is private and only invited donors and volunteers (teachers) can access the platform to manage and track their contributions and activities.

Shipped

NifftyFeatured

Niffty is a community-driven marketplace dedicated to empowering individuals and businesses by connecting them with skilled professionals across a wide range of services.

Shipped

Career History

Davos Asia Capital Sdn Bhd | Cognixus Technologies Sdn Bhd

Kuala Lumpur, Malaysia

  • Senior Software Engineer — 2023-08 to 2026-08
  • Software Engineer — 2021-05 to 2023-08

  • Architected & Standardized Development Frameworks: Established company-wide Flutter standards using the BloC pattern and developed a centralized TypeScript library for the company’s monorepo/microservices architecture, powered 10+ projects and streamlining RPC/API integrations.
  • Web3 & Blockchain Initiatives: Largely contributed to the company’s transition into Web3 by building a Nuxt.js ecosystem integrated with Go Ethereum (Geth); engineered complex backoffice tools for 40+ users featuring real-time gas fee calculations, automated smart contract payouts, and wallet management.
  • Project Recovery & Rapid Deployment: Successfully salvaged the Niffty.com marketplace project after a 2-year vendor failure, refactoring core peer-to-peer hiring functionalities and achieving a full market launch within 3 months of takeover.
  • Automated CI/CD & Security Infrastructure: Modernized mobile deployment by implementing Fastlane and Jenkins on on-premise macOS servers; designed a secure, branch-based credential management system using Gerrit to handle Apple certificates across multiple teams.

Zchwantech Sdn Bhd

Petaling Jaya, Malaysia

  • Mobile App Developer — 2020-04 to 2021-05

  • Advanced Native Integration: Developed high-performance custom video player modules using Swift 5 and Kotlin to support advanced gesture-based seeking, bridging them into React Native to overcome existing plugin limitations.
  • Architectural Optimization: Re-engineered existing React Native applications by implementing Redux-Saga, significantly improving state management predictability and team debugging efficiency
  • Android System Engineering: Designed a persistent Kotlin-based background service to intercept SMS OTPs and sync with merchant backends, ensuring high reliability even when the application was terminated by the OS.
  • Cross-Platform Portfolio Growth: Utilized Unity to customize and rebrand mobile gaming applications for rapid deployment, successfully expanding the company’s official app store profile and market presence.

Red Dragon Technology Sdn Bhd

Petaling Jaya, Malaysia

  • Full Stack Developer — 2019-03 to 2020-04

  • Full-Stack Lifecycle Management: Owned the end-to-end development of mobile projects (concept to support), delivering cross-platform social media and e-commerce apps using React Native.
  • POS System Innovation: Developed a specialized Flutter POS application featuring automated remote server synchronization and seamless hardware integration with thermal printers.
  • Backend Architecture: Designed and implemented a scalable Laravel backend specifically structured to handle complex multi-level marketing (MLM) hierarchical data and commissions.
  • Agile Collaboration: Provided critical cross-functional support in a lean development environment, ensuring the timely release and maintenance of high-priority internal and client-facing products.

Bumbung.co

Petaling Jaya, Malaysia

  • Backend Developer (Internship) — 2018-12 to 2019-03

  • Developed a full-stack MVP in Ruby on Rails to support a major corporate shift in product direction.
  • Streamlined UI/UX by migrating to Bootstrap and refactoring CSS, reducing technical debt and improving visual consistency.
  • Drove organic traffic growth for Bumbung.co by implementing technical SEO best practices and enhancing on-page performance.

Education

Sunway University

Bachelor of Science — Computer Science

2016-03 to 2019-02

Sunway College

Australian Matriculation (AUSMAT) — Foundation in Science

2015-03 to 2015-12

Sirius Scholar Study Skills (Now MITstem International School)

O Levels IGCSE — Secondary Education

2011-01 to 2014-12