Zhang is available for hire

Zhang Ruiyang

Verified Expert in Engineering

Software Developer

Location

Singapore, Singapore

Toptal Member Since

June 12, 2020

Zhang is a high-performing software engineer, a CFA, and an Associate of the Society of Actuaries (ASA). He has a strong background in mathematics, finance, and cryptocurrency, and was on the team that won the SAFU Blockchain Pre-Hackathon in 2019. His proficiencies include architecture design, complex algorithms, Unity 3D builds, integrations, testing, navigation, modeling, and upgrades. He enjoys writing high-quality code that delivers outstanding results for clients.

WebSockets Web Development Integration Front-end Web Scraping Responsive UI Fintech Consultant Full-stack Security Full-stack Development Artificial Intelligence (AI)Data Scraping Ajax Cryptocurrency Web3

Portfolio

Continuum Works Inc.

Solidity, Blockchain, Web3.js, Ethers.js, Truffle, Front-end Development...

DeFi Startup

Blockchain, Solidity, Solidity Assembly, Ganache, Hardhat, Truffle, Etherscan...

Juvo Mobile

Python, Node.js, Ruby on Rails (RoR), Go, React, JavaScript, Kubernetes, Docker...

Experience

Java - 8 years React Native - 7 years React - 7 years Ruby on Rails (RoR) - 4 years Ruby - 3 years Python - 3 years Node.js - 3 years Go - 3 years

Availability

Full-time

Preferred Environment

IntelliJ IDEA, Generative Pre-trained Transformers (GPT), OpenAI Gym

The most amazing...

...Unity3D-based head unit software I've developed ushered out a key algorithm for an investment company to intelligently allocate loans across investors.

Work Experience

Web3.js Blockchain Developer

2022 - 2022

Continuum Works Inc.

Designed and developed Web3.js features within our platform and help to create our token economy by building mechanisms to reward and transfer.
Participated and helped coordinate and come up with architecture design on gamification and tokenomics.
Helped engagement in the community by creating a bot to give rewards to community members as an incentive program.
Created ERC20 and ERC721 tokens for the ecosystem for learners on the platform. Devised a way to automatically issue the NFT to the learner.
Wrote a series of smart contracts in Solidity with Hardhat, Foundry, etc., with functionality like airdrop, governance, tokens, and value exchange.

Technologies: Solidity, Blockchain, Web3.js, Ethers.js, Truffle, Front-end Development, Tokenomics, Koa, React Redux, OpenAI GPT-4 API, OpenAI GPT-3 API, Games, Stripe, Google Analytics, Webflow

Consultant

2021 - 2022

DeFi Startup

Developed a smart contract for creating ERC20 token to represent index loans to create a secondary market; deployed and tested on Kovan, using Chainlink to get the real-time price of primary loan market tokens relative to stable tokens.
Created a vault to host different ERC20 and ERC721 tokens and calculate the real-time price of the vault and mint index tokens based on the vault balance.
Created a staking algorithm of reward tokens based on the amount of tokens staked in the vault—the tricky part is the base token is ERC20. The reward cap is defined for each base token so the ERC20 is overriden so the cap is kept track of.

Technologies: Blockchain, Solidity, Solidity Assembly, Ganache, Hardhat, Truffle, Etherscan, Ethers.js, Web3.js, Remix IDE, React, MongoDB, Express.js, Redux, Architecture, APIs, Swagger, TypeScript, HTML5, Angular, CSS3, WebSockets, Django, GitLab, Spring Boot, Unity3D, Amazon EBS, Next.js, NPM, Git, JSON, Ajax, EB GUIDE, Apollo Server, Axios, Flutter, Kubernetes Operations (kOps), Less, Amazon Kinesis, GitHub, Amazon S3 (AWS S3), PyTorch, Scikit-learn, SCSS, Ethereum Smart Contracts, Trade Finance, Excel VBA, Apache Kafka, AWS SDK, LaTeX, Confluence, CFA Level 3, jQuery, Bitcoin, Solana, Security, Front-end, MVC Frameworks, AWS Lambda, Decentralized Finance (DeFi), Amazon EC2, Reports, PHP, Mobile Web, Fintech Consultant, Cryptocurrency, Front-end Development, ASP.NET Core, Minimum Viable Product (MVP), Tokenomics, Koa, React Redux, Software Architecture, Mobile Apps, Stripe, Cloudflare

Senior Software Engineer

2019 - 2021

Juvo Mobile

Restructured the existing codebase into a microservice architecture. Refactored the codebase and extracted the communication logic to different carriers from the Rails engine to a separate standalone Go microservice.
Utilized GRPC protocols to bridge the existing base service to the new spin-off microservice. Architected the schema and project structure of the microservices.
Collaborated with the back-end and design teams to build the front end of the service. Used React, Redux, Next.js, and Rebass as the primary front-end toolkit and D3.js as the graph presentation facility.
Wrote a standalone microservice on our partner side to sanitize data inflow and outflow. This included anonymizing the MSISDN of the user by inbound encryption and outbound decryption or replacement of specific information on request and response.
Designed and implemented the project structure and functions of a server working as a gateway in Go.
Delivered a user-friendly configuration file in YAML to allow users to define the patterns of requests they want to match and locations to replace or encrypt/decrypt in the request or response.
Created a locating strategy to allocate the place for an operation to perform the desired sanitization on path, query, or body with key-value pair, JSONPath, or XML.
Implemented different load balancing strategies, including simple, round robin or weight, or power of two random choices, fair, sticky sessions, or sticky path.

Technologies: Python, Node.js, Ruby on Rails (RoR), Go, React, JavaScript, Kubernetes, Docker, MERN Stack, NoSQL, Microservices, Amazon Elastic Container Service (Amazon ECS), SQL, Full-stack, Amazon Web Services (AWS), CSS, MongoDB, Express.js, Redux, Architecture, APIs, TypeScript, HTML5, CSS3, Django, GitLab, Unity3D, Amazon EBS, Next.js, Django ORM, Git, JSON, Ajax, Axios, Stripe API, API Integration, Technical Leadership, Flutter, Mobile Development, Kubernetes Operations (kOps), Less, Amazon Kinesis, GitHub, Amazon S3 (AWS S3), PyTorch, Scikit-learn, SCSS, Ethereum Smart Contracts, Trade Finance, Excel VBA, Apache Kafka, AWS SDK, LaTeX, gRPC, jQuery, Banking & Finance, Nuxt.js, DigitalOcean, Security, Front-end, MVC Frameworks, AWS Lambda, Amazon RDS, Tailwind CSS, Redux-Saga, Web Development, PHP, Figma, Responsive UI, Mobile Web, Shopify, Cloud Firestore, Front-end Development, ASP.NET Core, .NET, Azure, Full-stack Development, Styled-components, Koa, React Redux, Software Architecture, ETL, Data Engineering, Amazon Cognito

CTO

2019 - 2020

CliquePass Singapore

Developed an online registration portal http://cliquepass.com/ for partners to join on our education platform. The component including stepped procedure design and signature recording.
Developed a mobile app using React Native, including location-based services, course displays, social networking functions, enabling the sharing of one's favorite courses with friends, and the registration of courses.
Included a loyalty and a payment system into the codebase.
Automated deployment using the latest CI/CD technology. Streamlined the process with Git commit.
Prepared knowledge for the presentation layer/container segregation in React Design and npm packages, including navigation, authE, and authO modules.
Delivered seamless and pixel-perfect translation of wireframe from Zeplin design and storyboard. Optimized performance on every level, including back-end cache, API optimization, and image compression.
Chose the best back-end technology to support, including the Golang framework, Beego, Gin, Mutex, or Ruby on Rails, Pythonic approach including Flask, Django, or a streamlined product like Firebase.
Used AWS to host the service. Set up EC2 and EBS with VPC to secure the communication and Route53 to assign the Elastic IP a domain.

Technologies: Ruby on Rails (RoR), React Native, Jira, CI/CD Pipelines, HTML, Bootstrap, MongoDB, Express.js, Redux, Architecture, APIs, Storybook, TypeScript, HTML5, Angular, CSS3, Django, Java 8, Spring Boot, Unity3D, Next.js, NPM, Django ORM, NumPy, Git, JSON, Ajax, Apollo Server, API Integration, Technical Leadership, CTO, Mobile Development, Less, Amazon Kinesis, Amazon S3 (AWS S3), PyTorch, Scikit-learn, Jenkins, SCSS, Trade Finance, Excel VBA, Apache Kafka, AWS SDK, LaTeX, Confluence, Fintech, Banking & Finance, Mathematics, Solana, Front-end, MVC Frameworks, Amazon RDS, Amazon EC2, Reports, C#.NET, Front-end Development, .NET, Full-stack Development, Minimum Viable Product (MVP), React Redux, Software Architecture, Mobile Apps

Senior Full-stack Developer

2018 - 2019

Funding Societies

Developed a command center (a central control system for all related microservices API) using Angular CLI.
Participated in core service upgrades, including member-services, finance services, and wallet-services deployed on AWS cloud using Node.js, Golang, and C#.
Built an auto allocation investment feature, with member services CRUDing the auto allocation settings and finance. The service of allocating the loan amount on each investor was based on their credit score, loan quantum, and loyalty tiers.
Performed technical support and consulted business teams on the financing flow. Assisted with emergence.
Developed notification services to digest information from Amazon Kinesis Streams and trigger the corresponding audience, using SMS, email, and Firebase messages based on the designed protocols and settings.

Technologies: React Native, React, Angular, Go, Python, Java, Node.js, C#, MongoDB, Express.js, Redux, Architecture, Swagger, Storybook, Design Systems, TypeScript, HTML5, CSS3, Django, Java 8, GitLab, Spring Boot, Unity3D, Amazon EBS, Next.js, NumPy, Git, EB GUIDE, Apollo Server, Axios, Stripe API, API Integration, Mobile Development, Kubernetes Operations (kOps), GitHub, Amazon S3 (AWS S3), Scikit-learn, Ethereum Smart Contracts, LaTeX, Confluence, gRPC, CFA Level 3, jQuery, Banking & Finance, Mathematics, Microsoft SQL Server, Front-end, MVC Frameworks, Amazon EC2, Django REST Framework, Amazon DynamoDB, Decision Trees, Integration, Responsive Web Apps, Adaptive Design, ASP.NET, Front-end Development, Full-stack Development

Software Engineer

2016 - 2018

Works Applications Co., Ltd.

Achieved, on average, an "A" grade for the design and documentation of a web-based human resource management and inventory system. Wrote catalogs regarding documentation about the merits and features of the software systems.
Created HR and inventory system business solutions to smoothen the user flow and cater to different use cases. Implemented these systems with jQuery, HTML5, Bootstrap, and a pre-defined database library.
Utilized Google Closure and Spring to design a highly usable data manipulation and maintenance page.
Delivered full-stack development including user flow design, user interface design, back-end implementation, client-side implementation, component design, and data base interaction.
Generated code for data the maintenance page of different data access objects using Spring Roo. Developed functions that allowed the showing, editing, importing, exporting, and adding of data.
Utilized client-to-server web socket communication and maintained the observer for information updates on both sides.
Channeled information among different application servers to sync data and share resources using Kafka.
Wrapped a Spring template and incremented features such as big file transfers and trans-application entity transmissions.
Decorated the Jackson library to provide a stable configuration, including the addition of a serializer and deserializer to other products.
Configured the mail server to send emails to mass recipients with blacklists or other functions. Maintained a stable flow of tasks in a given thread. If a request has not responded within a certain time frame, it will reject this task.

Technologies: Node.js, Thymeleaf, Google Closure, Spring, Java, Express.js, Redux, Design Systems, TypeScript, CSS3, Amazon EBS, NPM, Django ORM, NumPy, JSON, EB GUIDE, Apollo Server, Jenkins, Confluence, gRPC, Front-end, ASP.NET, WordPress

Software Engineer

2013 - 2016

Continental Automotive Singapore

Integrated and tested the infotainment system. Created an average of two quick prototypes and proof-of-concepts each week.
Designed, documented, and ran the test suites. Developed an automatic script to generate flashing files that could update and flash the hardware through a USB interface with a batch file and .NET frameworks saving more than 90% of the workflow time.
Implemented and tested enhancement feature requests to improve the product functionality for the Ford project. Developed an automatic testing framework and test suite for modules such as board computers, scroll bars, trip menus, and trip resets.
Drafted requirements documentation. Finished the test report and implemented automotive software with Unity3D for the HMI Framework and tool.
Evaluated and integrated to iMX6D. Designed and implemented modules, including media browser, skinning, language support, radio list, warnings, weather, menus, and board computers.
Participated as a key team member in the Unity3D group designing software architecture and integrations.
Solved framework setup issues such as DPool, storyboards, communication, events, animations, and HMI design. The team won first place and obtained high compliments from the judge.
Developed a man-machine interface using the embedded presentation framework. I designed and implemented EB GUIDE plugins, checks, macros, and widgets as an expert in EB GUIDE HMI design and tooling with Java, C#, and C++.
Implemented modules like navigation, off-road, lap timers, Hill Down, and control. Expert in the XML approach in modeling design.

Technologies: C#, Python, MonoScript, XPath, C++, XML, EB GUIDE, Java, Git, Stripe API, Jenkins, Front-end, Healthcare

Experience

Clique Enterpreneurship

https://github.com/ryonzhang/clique

Clique is a company under my name that uses an innovative approach of allocating additional educational resources to students in need. It involves a promotional page for education providers for registration, a mobile app with role segregation to onboard tutors, scheduling options, location-based filtering, and loyalty services.

Juvo Dashboard and Relevant Back-end Services

https://dashboard.juvo.com/

The project connects all important components of an airtime lending platform, providing the functionality of configuring campaigns, reviewing the metrics and statistics, checking the user information and their loan status, and modifying the relevant data entry. The project front-end uses React in TypeScript and Redux to control the data flow, and the back-end uses Ruby on Rails and Go orchestrated by Kubernetes.

Alloyx Smart Contract and Application

https://app.alloyx.xyz/#/dura

The Alloyx platform is composed of React and web3 packages and it integrates with many decentralized finance protocols, including Goldfinch, Maple Finance, and ClearPool. It creates the index token in ERC20 based on the pool's asset value, which provides liquidity for loan protocols that have a long lockup period and provides reasonable diversification on the portfolio. The back end uses Node.js, and the smart contract uses Solidity.

Master Maintenance on Data Manipulation

https://www.worksap.sg/

Used Google Closure and the Spring Framework to design a highly usable data manipulation and maintenance page. The full-stack development included a user flow design, user interface design, back-end, and client-side implementation, component design, and database interaction. I used Spring Roo to generate a code for a data maintenance page of different data access objects. Development functions include showing, editing, importing, exporting, and adding data.

PokerGo Website and Back-end

https://www.pokergo.com/

The project includes multiple back-end services, including a video service that handles all video-related data, subscriber management, payment gateway, daily job-keeping database integrity, and content management and the front end uses Vue, CSS, and HTML. The main language of the back end is using Go.

Bang The Table

https://granicus.com/solution/govdelivery/engagementhq/?utm_campaign=btt_redirect&utm_medium=referral&utm_source=bangthetable

The project focus on community management with multiple functionalities of event organization, voting, user management, and pooling support. The back and front end both use Ruby on Rails and include Docker Compose to link multiple peripheral tools like Redis and MongoDB.

Podcast Social Network Software

https://syncify.landen.co/

This project uses React Native to set up a social network software where users can search podcasts based on the producer and category. The player could comment on the playing track with their thoughts, follow friends' podcasts, and read their comments.

Continuum App, Learn to Earn

The project is a Web 3.0 learn-to-earn platform and the app uses tokenomics and gamification strategies to create an interactive React Native app to present a short-video form of learning content, where, by dedicating themselves to learning on the platform, the learner will be rewarded with ERC20 tokens, which can be changed to stablecoins through other decentralized finance protocols.

NeonCEO - LinkedIn-like Platform

This project is prototyping a LinkedIn-like platform to provide a one-stop talent-hunting portal for startups. The back end uses Node.js, and the front end uses React. The functionality includes searching for talent profiles, and integration with many third-party software, including a tax portal, Miro, and live-meeting features.

FBA-related Chrome Extension

It is a pricing tool for the Amazon seller, which extracts information from Ajax calls for products, including all prices related to a product, including FBA and merchant offers. The extension provides a configuration panel for sellers to set based on the product's ranking. It is an arbitrage tool to give options for sellers to set based on defined rules and explore potential opportunities easily.

Skills

Languages

Go, Java, Python, Ruby, JavaScript, HTML, HTML5, CSS, SCSS, Less, XML, TypeScript, Solidity, CSS3, PHP, C#.NET, GraphQL, C++, C#, Excel VBA, Java 8, SQL, XPath, Solidity Assembly, Rust

Frameworks

Ruby on Rails (RoR), React Native, Django, Beego, Angular, Bootstrap, Swagger, Nuxt.js, Tailwind CSS, Django REST Framework, ASP.NET, ASP.NET Core, .NET, Koa, Spring Boot, Unity3D, gRPC, Express.js, Next.js, Truffle, Flutter, Redux, Spring, Thymeleaf, Hardhat, Ruby on Rails 5, Ruby on Rails 4

Libraries/APIs

Node.js, React, Vue, jQuery, Web3.js, REST APIs, Sidekiq, Redux-Saga, React Redux, Stripe, Django ORM, PyTorch, Scikit-learn, NumPy, Shopify API, Twilio API, Google Closure, Stripe API

Tools

Amazon Elastic Container Service (Amazon ECS), Pytest, Bitbucket, Webpack, Figma, Amazon Cognito, Google Analytics, ChatGPT, Amazon EBS, AWS SDK, MATLAB, LaTeX, Spring Roo, GitHub, GitLab, Jenkins, Git, Confluence, NPM, OpenAI Gym, Jira, IntelliJ IDEA, Ganache, Etherscan, Remix IDE

Paradigms

Test-driven Development (TDD), Database Design, REST, ETL, Microservices, Mobile Development, CQRS, Parallel Programming

Platforms

Blockchain, Kubernetes, Firebase, DigitalOcean, Shopify, Amazon EC2, WordPress, Webflow, Ethereum, Unix, Apache Kafka, Docker, Amazon Web Services (AWS), Blockchain Platforms, AWS Lambda, iOS, Azure, Google Cloud Platform (GCP), Chrome OS

Storage

JSON, MySQL, PostgreSQL, Redis, Amazon DynamoDB, MongoDB, Amazon S3 (AWS S3), Cassandra, NoSQL, Cloud Firestore, Elasticsearch, PSQL, Microsoft SQL Server

Industry Expertise

Banking & Finance, Project Management, Healthcare

Other

Ethereum Smart Contracts, Ajax, Axios, Apollo Server, Amazon Kinesis, CFA Level 3, Fintech, Mathematics, Smart Contracts, Non-fungible Tokens (NFT), Kubernetes Operations (kOps), Full-stack, Architecture, Technical Leadership, API Integration, APIs, WebSockets, Storybook, Design Systems, Solana, Security, Front-end, MVC Frameworks, Decentralized Finance (DeFi), Ruby Gems, Software Architecture, General Ledgers, Progressive Web Applications (PWA), Scraping, Web Scraping, Amazon RDS, Web Development, Decision Trees, Responsive UI, Mobile Web, Integration, Responsive Web Apps, Adaptive Design, Fintech Consultant, Cryptocurrency, Front-end Development, Full-stack Development, Minimum Viable Product (MVP), Styled-components, Tokenomics, Mobile Apps, Data Engineering, OpenAI GPT-3 API, Lambda Functions, Web3, Analytical Dashboards, Artificial Intelligence (AI), Games, Cloudflare, OpenAI, Data Scraping, Trade Finance, Machine Learning, Derivatives, Ethers.js, MERN Stack, Jira Align, CI/CD Pipelines, CTO, Bitcoin, Reports, Generative Pre-trained Transformers (GPT), OpenAI GPT-4 API, EB GUIDE, MonoScript, Computer Science, Electrical Engineering, ERC-20, ERC-721, Web Extensions, Solution Architecture, Algorithms, Finance, Networks, Reinforcement Learning, Deep Learning, Natural Language Processing (NLP), Data Structures, Electronics, GPT

Education

2019 - 2020

Master's Degree in Computer Science

University of Texas at Austin - Austin, Texas, USA

2008 - 2013

Bachelor's Degree (First-class Honors) in Electrical and Electronic Engineering

Nanyang Technological University - Singapore, Singapore

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