Rufus Tsai (蔡宗儒)

Introduction

Backend Software Engineer with 10+ years of experience building web systems across Taiwan and Japan. Specialized in PHP Laravel and Node.js, with hands-on expertise in financial transaction systems, cloud infrastructure (AWS), and CI/CD pipelines. Brings an additional edge as an engineer with direct Project Management experience — having led cross-functional teams of up to 15 people — enabling effective collaboration between business stakeholders and engineering teams. Trilingual in Mandarin Chinese, Japanese (JLPT N1), and English; with proven experience in cross-cultural, Japan-facing environments.

Work Experience

PHP Laravel Engineer - Quad Inc., Taipei City

June 2024 - Present

• Supported overseas headquarters in developing and maintaining a cross-border payment platform, covering PHP Laravel backend and React admin UI features.
• Developed a merchant fund risk management mechanism covering fund holds, automated unlocking, and exception-rule handling, strengthening the platform’s fund control.
• Built scheduled transaction risk review and monitoring workflows to help identify abnormal transactions or those requiring manual review earlier.
• Optimized a critical operational query, reducing user activity log lookup time from 22 seconds to 2–3 seconds.
• Developed member rewards, notifications, and marketing automation services using Redis, queues, and scheduled jobs, increasing daily active users by about 5%.
• Built a Slack Bot to monitor key transaction metrics and troubleshoot issues (Postman verification, AWS CloudWatch log tracking).
• Integrated Google OAuth 2.0 and reCAPTCHA v3 into registration and login flows to enhance identity verification and prevent bot attacks.
• Wrote unit and functional tests covering Service, Controller, and exception handling to ensure stability and maintainability under high transaction volume scenarios.
• Tools used: PHP Laravel, AWS (CloudWatch, S3), GCP (reCaptcha, OAuth2.0), Docker.

Software Engineer - Access Taiwan Lab Software Development, Taipei City

August 2022 - August 2023

• Developed RESTful APIs for a smartwatch management backend, wrote test code, maintained the product, and performed issue troubleshooting.
• Introduced AWS CodePipeline to implement CI/CD automated testing and continuous integration, reducing deployment time from 1 business day per week to 1 hour, cutting operational costs while improving system stability.
• Quickly took over project development after the previous engineer’s departure and mentored Vietnamese engineers to maintain delivery momentum.
• Tools used: Node.js, Ansible CD, AWS (CodePipeline, EC2, Load Balancer), Docker.

Project Manager - Access Taiwan Lab Software Development, Taipei City

December 2020 - July 2022

• Gathered requirements, created project plans, managed costs, coordinated human resources, confirmed development specifications, wrote documentation, and managed risks.
• Led the Taiwan team (up to 15 members) to collaborate with the Japanese team on major company projects, tracked progress, removed blockers, handled project crises, and ensured on-time delivery to sustain the company’s primary revenue.
• Served as leader of a 4-person team in an internal product pitch competition, proposing an app to address exploitation of migrant workers by brokers — won first place twice among six competing teams.
• Promoted and improved the internal knowledge-sharing session system, facilitating cross-team communication.

(Part-time) Engineer - Taiwan Ocean Conservation and Fisheries Sustainability Foundation, Taipei City

July 2020 - May 2023

• Maintained the Taiwan Seafood Guide and introduced version control.
• Led the development of the MCS Fisheries Reporting Database system, including requirement confirmation, feature planning, database design, framework selection, and environment setup. Introduced a Git branching strategy and Trello kanban for progress management.
• Refactored the table architecture and data of the legacy Fish Database and introduced PHP Laravel seed/migration and version management tools.
• Enhanced system security by analyzing overseas attack attempts from logs, and adjusting Linux server configurations to restrict unauthorized foreign access.
• Tools used: PHP Laravel, JavaScript.

Engineer - Novelworks, Osaka, Japan

June 2019 - January 2020

• Interviewed Japanese client requirements, developed applications for the business management platform kintone (used by 37,000 companies), and deployed to AWS Lambda.
• Researched and implemented OAuth2.0 authentication.
• Maintained the company website, including updating SSL certificates and managing AWS EC2 servers.
• Hosted kintone promotion seminars.
• Tools used: Node.js, AWS (EC2, Lambda).

Backend Engineer - Cookbiz, Osaka, Japan

June 2018 - May 2019

• Developed and maintained the cookbiz food & beverage staffing platform and its backend (1.5M users/year, 30K job listings, 10K+ partner companies).
• Wrote AWS CloudFormation scripts to optimize infrastructure provisioning, and improved Vagrant development environment scripts.
• Tools used: PHP (proprietary framework, CakePHP, Yii), AWS (CloudFormation), Vagrant.

Engineer - Radical-Opti, Osaka, Japan

July 2015 - April 2018

• Developed a beauty appointment booking system for client Eyelash Salon Blanc.
• Developed the b-league basketball league merchandise e-commerce website using the ec-cube open-source e-commerce framework.
• Developed the iDA fashion industry job listing website, including a contact-us email sending feature and SEO adjustments.
• Tools used: PHP (CakePHP), JavaScript, Vagrant, Docker.

Project Engineer - EasyUse Digital Technology, Taipei City

May 2012 - October 2014

• Customized digital bill management and marketing management systems for major domestic financial and insurance companies.
• Wrote Windows services, scheduled tasks, and executable files.
• Developed bill and marketing advertisement layouts using HTML and ASP.NET.
• Main responsibilities included evaluating development schedules, product development, client system go-live, and ongoing maintenance.
• Tools used: C#, ASP.NET.

Education

Master of Marketing

Virginia Commonwealth University, Virginia, U.S.A.
Graduation: May 2011

Bachelor of Information Management

Tamkang University, Taipei City, Taiwan
Graduation: May 2006

Skills

Category	Details
Backend Languages	PHP (Laravel), Python, Golang, Node.js
Frontend Development	JavaScript, HTML, CSS (SCSS), Vue.js
Database Management	Redis, MySQL, PostgreSQL, MongoDB
Infrastructure	Docker, Vagrant
Version Control	Git, GitHub
Cloud Services	AWS (EC2, S3, Lambda, API Gateway, CodePipeline, CloudWatch), GCP
Others	Project Management, Agile Development; Cross-cultural collaboration between Japan and Taiwan

Projects

Flash Card

• A Next.js flashcard service with AI-generated decks (AI Deck), Clerk authentication and paid access control, using Drizzle ORM with Neon (serverless PostgreSQL).
• Key features: deck management, flashcard management, AI deck generation (via Vercel AI SDK and OpenAI gpt-4o-mini), access and billing control (Clerk Billing), per-user data isolation (Clerk userId), i18n.
• Source code on GitHub

Simple Bank

• A lightweight banking backend built with the Golang Gin framework, exposing RESTful APIs, using sqlc as the ORM with PostgreSQL, and GitHub Actions for CI/CD with automated testing and deployment.
• Core features: account opening and transfers.
• Source code on GitHub

Languages

• Mandarin Chinese (Native)
• English (Working proficiency)
• Japanese (JLPT N1 Certified)

Interests

• Finding great food via Google Maps
• Snowboarding
• Guitar