Sung Cho - Contracting
I am available for hire as a contractor. Here are some of the things I can achieve for your company:
- Solve complex full-stack problems in production. At Dnote, a big technical challenge was to sync users’ notes across multiple devices. I wrote a scalable state-based replication algorithm to reliably sync states across an arbitrary number of offline-first nodes with an eventual consistency. On top of that, I have also designed and implemented a secure, end-to-end encrypted cryptosystem that protects users’ privacy with zero knowledge encryption while still allowing users to synchronize the data.
- Optimize your frontend performance. At Luxury Escapes, the checkout page built with React was slow to render and respond. I sped up the page render by 40% and responsiveness by 35% by carefully benchmarking the app and writing a state machine. You can learn more in this case study.
- Wrap your web application into a mobile app. Simply Wall St had a challenge in which its mobile application was falling behind the web application built with React and TypeSciprt. I have solved the challenge by delivering a new mobile application that wraps the web application in a WebView and consumes Native SDKs through a JavaScript bridge. I have also turned the web application into a Progressive Web App. You can learn more in this case study
- Rewrite in Go or node.js. I have re-platformed a number of enormous legacy applications running PHP or .NET into node.js microservices and React frontend. You can read more in this article.
- Evangelize products among technical communities. At Dgraph, I built applications using the product, gave talks and wrote articles, spreading the technology and help growing the fledgling community.
- More things. Software is my passion and I strive to achieve a higher mastery and deliver greater impact. I can bring the same attitude to your company.
I have extensive experience with a number of technologies in production, notably JavaScript, Go, React and Ruby. Here is my GitHub profile, a resume, and talks with links to videos.
Rates
I am open to both short term and long term contracts.
Previous engagements
Luxury Escapes
Rearchitected the purchase flow in a brittle internal React web application into a scalable and extensible solution handling >AU$100 million of purchases yearly.
Using node.js microservices and React, extended a hotel-only travel business platform into an integrated flights & hotel bundling business. Optimized a checkout process of a React application by 40%, handling >AU$300 million purchases yearly.
Sung redefined what we believed we could achieve through a combination of both extremely high-quality code & fast delivery.
Timothy Downs, Head of Engineering @ Luxury Escapes
Simply Wall St
Based on a web application built with React and TypeScript, delivered a mobile application by wrapping the application in a web view and exposing native SDKs to the JavaScript runtime.
While doing so, also enabled the web application to be used as a Progressive Web App (PWA), thus strengthening the mobile presence of the company while helping users access the product more easily.
We were quite impressed by Sung’s diligence and attention to detail throughout the project. He gave us very accurate and honest timelines throughout and completed them all on time, if not before they were due. Even when faced with teething problems, Sung was incredibly resourceful in troubleshooting and working around any technical blocking issues.
We will definitely keep Sung in mind for any future projects where we need fast, consistent and high quality outside help.
Jabin Bastian, Chief Technology Officer @ Simply Wall St
Dgraph
Designed, and built a GUI for a distributed graph database using React and Go. Shipped an open source clone of StackOverflow using Dgraph, React and node.js.
Designed, built, and maintained the official docs website and an interactive tutorial.
Style Atlas
Built Ranges, a feature that replaces spreadsheet for designers and fashion labels.
Products
Dnote
Designed and built a free and open source, a commercial personal knowledge base software supporting clients in web, command line, browser extensions, and an IDE plugin.