• Used Solidity.js to write and deploy EVM-based Upgradeable Smart Contracts and create features for users to interact with their NFTs. Developed on Vechain, BSC, Ethereum, and Polygon. • Created NFT based features that included: investing ERC20 tokens to level-up NFTs, NFTs sharing their invested tokens with other NFTs, running multiple marketing events of airdropping NFTs & tokens to users, running NFT-Vending-Machine events that allowed users to purchase & win random NFTs, running events for VIP whitelisted wallets, created an OpenSea-like marketplace that supported ERC20 & native tokens, created an NFT portal that converted any NFT collection to be integrated into VimWorlds gaming ecosystem.• Created Smart Contract system of Controller & Data linked contracts to easily upgrade contract features without losing contract data & Event data. Wrote contracts with batch functionality to save users gas fees.• Used Hardhat Typechain to generate custom Typescript Ethers.js bindings for contract functions for frontend developers to easily interact with deployed contracts. • Used Hardhat Typechain & Node.js to write backend scripts to pull, filter, and process on-chain data & run mass transactions on the blockchain.• Used Ethers.js to write cross-chain scripts to migrate entire VimWorld ecosystem (35+ contracts, >20K NFTs + supporting on-chain data) from Vechain to BSC chain.• Responsible for designing & executing cross-chain data migration process to migrate entire Vimworld NFT ecosystem from Vechain to BSC chain. Responsible for deploying company ERC20 token on BSC, Ethereum, and Polygon mainnet that passed Hacken auditing.• Found and fixed legacy bugs in existing contracts and removed security risks from contracts. Managed and set internal contract ownership and contract admin powers.• Used Slither for static analysis and Smart Contract Auditing. • Used Mocha/Chai + Hardhat for Smart Contract unit testing.

• Designed & implemented Golang REST-api for Cryptocurrency loaded debit card feature, using Echo framework for http server, complete with KYC data checks, CORS policies & rate-limiting features, and unit tests.• Designed & implemented Postgres Database business model for data storage & pulling/pushing data such as KYC data, and integrated with REST-api using go-pg, complete with row-locking & transaction rollbacks.• Implemented monitoring & alerting features into REST-api with Prometheus, and bug-tracking such as Sentry & Kibana.• Created Golang background services that update DB data & run on scheduled timer.• Designed & implemented Golang REST-api for Crypto-exchange bidding feature, including an internal crypto withdraw/deposit system.Stack: Golang, Echo, go-pg, Postgres, Docker, Kubernetes, Prometheus, Kibana, Sentry, Gitlab.

• Created REST-api & Internal Recruiter CMS app for Recruitment agency that allowed Managers to login/register & assign jobpostings to Recruiters as tasks & track task-completion.• Created multi-file upload/cloud storage/database processing feature with low network latency & high concurrency using multithreading.• Created MySQL Database system with multiple tables, primary/foreign key relationships, and one-to-many relationships for business model data storage and processing.• Created CORS polices, rate-limiting with gorilla-mux HTTP framework & paginated DB pulling endpoints with filtering features.• Created data-parsing service with multithreading for high-load database transactions.• Worked with Data Scientists to create DB stored procedures to clean/filter/process data collected by web crawlers.• Dockerized & deployed demo/staging/production servers for backend/web crawler apps using Docker & AWS ECS.

• Worked with a small startup to plan, develop and design their Android platform application from scratch that allows users to find and purchase family activity services either from an existing collection or using a custom request builder. Inbound and outbound requests (both in HTML, JSON, CSV format) are loaded via the backend process on RDS database.• Created a family activity builder from scratch where users can purchase and/or save custom requests to their account. Once saved, requests can be opened, deleted, and/or purchased again.• Created custom shopping cart and checkout integrated with BrainTree and a Node.js backend.• Created user custom request builder with location services via Google Maps and Places API.• Responsible for planning, documentation, wire-framing, design, and development of full Android application lifecycle. • Worked with cross-functional and international teams to design product architecture.• Built client-side cloud integration using Firebase and server-side REST integration via Volley and Fresco for faster networking and image loading services.• Improved performance/usability by Espresso & unit testing via LogCat/BugReporting.Stack: Java, Node.js, Express.js, MySQL, Python, AWS Kinesis, AWS RDS/EC2/S3, Google Firebase, Android SDK, Swagger, Postman, JWT Authentication, Git.

• Designed and developed responsive web app with business themed user interface.• Increased sales and attracted new clients by creating web business promotion distribution flow.Stack: Node.js, Express.js, HTML/CSS, Mocha, Google Maps API, Materialize, AWS EC2/S3, Git.