Node.js, Golang, PostgreSQL, MongoDB, Elasticsearch and React.js/Redux.
Backend development and infrastructure
CI/CD; dynamic schema management systems; authorisation and permission control services; high-performance ticket systems, message queues, and e-commerce systems.
Search engine migration and tuning, event-driven data loaders, auto reindex setups, and new queries.
PostgreSQL and MognoDB database tuning. Including indices and sharding.
Multi-layer cache design and control, including memory cache, Redis cache, and CDN.
Front-end development building e-commerce in-app web view pages, admin panels, and operation tools.
Back-end developer, Dcard, Jun. 2017 – present
The biggest social media app in Taiwan. (App store)
This position works closely with the infrastructure team members, data scientists, and product managers. Dcard is the most popular social media app in Taiwan.
Implemented dictionary compression utility for a high writing-load database with a 95% compression rate and 60% insert speed improvement.
Improved Elasticsearch performance and conducted new query implementation. Rewrote index mapping; as a result, the new index was reduced by 40%, allowing us to build an auto-reindex trigger.
Created the Node.js service template and CloudFlare worker’s template. Provided a quick and easy environment for developers.
Added or removed indices and materialised view for our PostgreSQL. Improved query performance. Reduced API response time to 400ms.
Analyse and optimise multi-layer cache, including service internal local cache, Redis cache, CDN, and CDN internal worker.
Constructed a dynamic server-side rule-based configuration service that now handles at least 100 different rules.
Developed a subscription feed service that handles thousands of new posts every hour and feeds to millions of subscribers.
Responsible for high-performance reporting service, 2020 presidential election chatroom, moderator system, personal feed system, and content management system for operation department.
Cooperated directly and efficiently with the sales department. Responsible for the scheduled ticketing system, check-in system, real-time participant calculations, and activity website. Developed a highly successful offline activity with the sales team, attracting over 10,000 participants.
Established a ticketing and gift delivery service, which handled 15,000 draw requests per minute at the peak time. More than ten thousands gift delivery campaigns were processed.
Responsible for advertisement system, e-commerce service (including the checkout process, in-stock management, and all web pages), and advertising post scheduling system.
Fandora Shop, Backend developer intern, 2015 Dec - 2016 Sep
Used Node.js/Express, MariaDB, AWS, and GraphQL. Directly mentored by CTO.
Worked on e-commerce back-end service. Redesigned and rewrote the entire system, with more than 60 endpoints rewritten. At least 100 admin endpoints were aggregated to GraphQL endpoint.
Built the delivery system that connected to a local delivery company and synchronised 40,000 package statuses daily.
Cooperated with a local bank to build a new subscription service.
Additional Knowledge and Interests
Oriental Institute of Technology - Department of Information Management.