Web Developer


Web Developer


Full Name

鄭景仁 / Chin-Jen Cheng


January 6, 1990




中文, English



3F, No.378, Nanxiang Rd.,

Luzhu District,

Taoyuan City, Taiwan, 33854


+886 931 077 193


4 years' experience as a web developer across front-end, back-end and some infrastructure. I can communicate and cooperate with others clearly. I've worked at startup and large company, so I know what should do in the different time by the growth stage of the company.

For more works I've done please visit my portfolio: jimmmmy.com/portfolio



HTML, CSS, JavaScript

  • 4 years experience
  • Familiar with HTML, CSS and more than 30 projects launched on production environment
  • ES6, Object-Oriented JavaScript

[Framework] React, Redux

  • Nearly 1 year experience
  • Have 3 projects launched on production environment with React and Redux

[CSS preprocessor] Sass, Stylus

  • 1 year experience
  • Have 1 projects launched on production environment with Sass and 3 for Stylus



  • 1 year experience
  • Have 4 projects launched on production environment
  • Have 2 side projects on GitHub
  • Dealing with concurrency problem
  • Keep learning with this elegance language


  • Nearly 1 year experience
  • Have 5 projects launched on production environment
  • Develop API with Express, Swagger
  • Write unit test with Jasmine, Mocha


  • 2 years experience and most of time was using WordPress to develop themes and plugins, more than 10 projects launched on production environment


  • CRUD
  • Indexing, partition

[NoSQL] MongoDB, Firebase

  • CRUD
  • Take benefit from Firebase to deal with real-time event by cloud trigger



  • Setting up environment by using Docker Compose

Google Cloud Platform

  • Handle cluster services by using Kubernetes Engine
  • Deploy services with Kubernetes and Docker
  • Handle event trigger by using Cloud Functions with Firebase


Dec.2017 ~ Aug.2018

工程師 / Engineer

工程師 / EngineerDec.2017 ~ Aug.2018

Outsourcing company. As a full-stack developer, I use Node.js, MongoDB, Express, React, Redux to deal with projects I've in charge for.

I'm involved with projects below:

  • Customer service system:
    Using Socket.io to build a total solution for customer and the company, include chat room, analysis system, reporting system. I'm in charge of develop chat room feature, include front-end and back-end.
  • Real-time chat system:
    Our goal is to make a Twitch-like website. I'm in charge of develop whole website from scratch, include front-end and back-end.
  • Strategy recommendation system in lottery game:
    I'm in charge of develop back-end logic, like lottery drawing calculation, and using Electron to build up client-side application.

Oct.2016 ~ Dec.2017

後端工程師 / Back-end Developer

後端工程師 / Back-end DeveloperOct.2016 ~ Dec.2017

Develop back-end API, design system architecture, cooperate with front-end and mobile application team.

I'm in charge of:

  • Back-end API development:
    By using Golang and MySQL, follow RESTful principle, building highly available system (5 million database record increase monthly, nearly 1000 users online at the same time).
  • Website crawler development:
    We need some data from other website for checksum, so we crawl other website densely and periodically. Considering our IP address may being block, we have several crawler server to avoid the checksum service break.
  • Develop API for mobile application:
    To integrate with existing API, I build a middleware to filter the data which only needed by mobile application. I also make several cache mechanism, no matter it is checked by timestamp or hash, these is all for decrease the transmission cost.

Mar.2016 ~ Sep.2016

專案經理 / Project Manager

專案經理 / Project ManagerMar.2016 ~ Sep.2016

Managed the progress of projects, contact with customers to help engineers and designers to accurately understand what customer needs.

I'm in charge of:

  • Project management (using Trello, Slack, TeamWeek, and Google Sheets).
  • Customer development.
  • System analysis and design.
  • Establish the sales kit.

Mar.2015 ~ Sep.2016

工程師 / Engineer

工程師 / EngineerMar.2015 ~ Sep.2016

Develop front-end and back-end for projects, and also maintained company's hardware and software.

I'm in charge of:

  • Build up website infrastructure (like VPS environment setting, DNS, database setting).
  • Develop a website by using WordPress (PHP + MySQL), depend on our customer, we customizing the WordPress module, like administrator dashboard, membership level system, email system, online shop, crowdfunding platform ... etc.
  • Design website layout and make it work perfectly by using HTML, CSS, JavaScript.
  • Develop payment gateway plugin for WooCommerce (AllPay, PayPal, ECPay, Pay2GO, Spagateway ...).
  • MySQL database tuning, SEO optimization.

Nov.2014 ~ Mar.2015

工程實習生 / Engineer Internship

工程實習生 / Engineer InternshipNov.2014 ~ Mar.2015

Assist in the development of projects.

What I've done in this position:

  • Develop Joomla's payment gateway API, using T-CAT (統一客樂得) Payment, wrote in PHP.
  • Develop WordPress plugin like Facebook LikeBox, Facebook Fan Page Album Transmitter ... etc, wrote in PHP.


Sep.2012 ~ Jan.2014

銘傳大學 / Ming Chuan University

銘傳大學 / Ming Chuan UniversitySep.2012 ~ Jan.2014

資訊工程研究所 / Institute of CSIE

Sep.2008 ~ Jun.2012

銘傳大學 / Ming Chuan University

銘傳大學 / Ming Chuan UniversitySep.2008 ~ Jun.2012

資訊工程系 / Department of CSIE