Draco Li
Verified Expert in Engineering
JavaScript Developer
Toronto, ON, Canada
Toptal member since April 14, 2020
Draco is a seasoned lead engineer with over 12 years of extensive full-stack experience in various industries, including online retail, web3, and AI insurance. As a founding engineer at Dots, Draco spearheaded the launch of highly acclaimed iOS apps, TwoDots (50+ million downloads) and Dots & Co (1.5+ million downloads within two days). He also served as the engineering lead at Loose Button, where he launched an online advertising network that grew to over $1 million in sales in three months.
Portfolio
Experience
- JavaScript - 10 years
- Ruby on Rails (RoR) - 6 years
- Node.js - 5 years
- TypeScript - 5 years
- React - 5 years
- GraphQL - 4 years
- C# - 4 years
- Go - 3 years
Preferred Environment
Xcode, Slack, Visual Studio Code (VS Code), Git
The most amazing...
...product I've collaborated on is called TwoDots. It ranked number one in over 100 countries on both the App Store and Play Store.
Work Experience
Senior Rails Developer (via Toptal)
Giftly Inc
- Developed the core multi-tier system for Giftly places, handling complex logic interactions, tests, and scheduled tasks to manage tiers for over 10 million Giftly locations.
- Achieved deep integration with Google Ads, including automated segmentation, Google Shopping syncing, and Google Analytics.
- Drove multiple growth initiatives at Giftly, increasing conversion and visits by over 80%. Key initiatives included implementing an A/B test framework, place tier system, and Google Shopping integration.
Full-stack Go/Node.js Engineer
Looka Inc
- Developed a proprietary AI-powered graphics editor integrating LLMs and RAG for intelligent design assistance, using TypeScript and React.
- Designed scalable back-end APIs in Go to support real-time design data synchronization, semantic AI-driven search, and modular template management.
- Improved rendering performance by 40% by optimizing canvas operations and minimizing re-renders in complex design workflows.
- Architected the collaborative engine for a live multi-user editing experience in the flagship business card editor, enhancing team productivity and user engagement.
Blockchain Developer
Kava Labs
- Served as the core contributor to the open-source Kava blockchain, a top 100 crypto project by market cap and a top 10 decentralized finance chain by TVL.
- Led the development of the EVM support for the Kava blockchain, unlocking over $200 million in TVL through new protocols.
- Developed a method to allow for MetaMask signing of Cosmos transactions, which enabled EVM users to interact with the Cosmos-based Kava blockchain.
- Demonstrated expertise in various technologies, including Go, Cosmos, Ethereum, MetaMask, and Web3.js.
Full-stack Developer
Next Jump
- Migrated outdated hotel and flight API services from PHP to Go successfully, resulting in a significant reduction of 65% in errors and a 20% decrease in latency.
- Designed and implemented a refined hotel search algorithm, leading to an impressive improvement of over 80% in booking search response time. Furthermore, the search results showed enhanced availability with an increase of 1.1x to 3x more returned prices.
- Identified and resolved bottlenecks in PHP and Go API services, ensuring a highly reliable and high-performing system. Implemented proactive issue detection and resolution through robust Kibana monitoring processes.
Senior Engineering Consultant
Restaurant Brands International
- Built and launched the Popeyes and Burger King rewards platforms across the US and Canada (Node.js back end and React front end).
- Led the development of the user data deletion and access requests using OneTrust and a custom-built AWS pipeline.
- Designed and implemented multiple user events tracking methodologies across all three RBI brands (Burger King, Tim Hortons, and Popeyes).
- Demonstrated expertise in serverless architecture using AWS Lambda, DynamoDB, AWS Step Functions, and SQS.
Engineering Lead
MasterHealth
- Led the engineering development of a cross-platform, subscription-based healthcare app on React Native and Node.js.
- Managed a team of engineers (local and remote) on the development of the back-end API (Node.js, TypeScript, PostgreSQL, and GraphQL).
- Oversaw the development and creation of a flexible program data database schema (via PostgreSQL) that allows the team to create new healthcare programs easily.
- Developed several powerful internal tools using Retool that allowed extensive real-time application and course data configurations.
Lead Architect
DollarOP
- Developed DollarOP, a lottery-based eCommerce shop with crypto payments and a live winner-drawing experience via a Rails background and a TypeScript/React front end.
- Designed and developed a unique purchasing process that allows users to purchase shares of an item via a credit card or cryptocurrency.
- Oversaw the launch of DollarOP, which saw over 1,000 users on the first day of the launch.
- Planned and architected the core online retail platform for DollarOP, including a GraphQL back end and a SPA for the client-facing retail platform.
Engineering Team Lead
Jerry
- Led a team of senior engineers to manage the development of the Jerry CRM system used by over 100 internal and external insurance agents.
- Collaborated with the leadership team to improve internal processes, code quality, and cross-team communication. This enabled us to double our engineering headcount within six months.
- Managed a remote development team of three engineers based in Lviv, Ukraine, to assist in CRM product development.
Staff Engineer
Playdots
- Led the development of back-end microservices to purchase tracking using Go workers for events processing via AWS SQS. This service is used in production by TwoDots (50+ million downloads) and Dots & Co (10+ million downloads).
- Contributed to diverse core back-end features, including player inventory syncing, weekly events, cheating detection, A/B testing, authentication, install tracking, and global leaderboard for over 1 million DAUs.
- Developed back-end services for player data syncing, authentication, install tracking, and multiple in-game event systems.
- Contributed to the architecture and development of Dots, TwoDots, Dots & Co, and multiple unannounced games.
- Created admin dashboards for in-game economy management (Ruby on Rails and AWS Elastic Beanstalk).
Engineering Lead
Loose Button (Acquired)
- Managed all technical developments and launched a number of services including a dashboard for large CPG brands, an online retail store, and a subscription service for tights.
- Developed the core analytics dashboard for the ad network, which grew from nothing to over $1 million in sales within three months.
- Improved overall hiring process for software engineers and established a formal performance review system.
Experience
TwoDots
https://apps.apple.com/us/app/two-dots/id880178264For the back end, I led the development of a microservice for purchase tracking, systems for player event data syncing, cheat detection, weekly events, global leaderboards, and an internal A/B testing platform.
For the game, I led the development of the level editor, weekly events, and multiple SDKs to interact with back-end microservices.
DollarOP
I was the lead engineer behind this project. I designed and developed both the back-end API and the SPA for the client-side retail store.
The back end uses GraphQL and WebSockets to enable flexible data retrieval and instant updates on the online store when purchases are made. The front end is built with React and is both interactive and performant. The web app also includes a live winning selection event that is built with the HTML5 gaming framework, Phaser.js.
Dots & Co
For the back end, I designed and built a player inventory syncing system and a platform to A/B test and provide data to the in-game economy.
For the game, I led the development of the level editor and built the weekly event system.
CertifyOS RDB Migration
https://www.certifyos.com/Migration of WordPress Blog Site to Next.js
https://www.weddingstylemagazine.com/Education
Bachelor of Commerce Degree in Commerce and Computer Science
Queen's University - Kingston, Ontario
Bachelor of Commerce Degree in Commerce and Computing
National University of Singapore - Singapore
Skills
Libraries/APIs
React, Facebook API, Node.js, Vue, REST APIs, X (formerly Twitter) API, Google API, Stripe, Stripe API, Social Media APIs, SQLAlchemy, Pydantic, Emotion Library, React Router, React Navigation, PayPal API, WebGL, AWS Amplify, jQuery, Web3.js, Sidekiq, Yelp API
Tools
Git, Amazon Simple Queue Service (SQS), Google Analytics, Amazon Simple Notification Service (SNS), AWS Step Functions, Jira, Confluence, Retool, Knex.js, Xcode, Sequelize, Prisma, React Apollo, Amazon Cognito, AWS AppSync, Terraform, Figma, Absinthe, Amazon CloudFront CDN, NPM, Slack, Flow, GoLand, MetaMask, Webpack
Languages
Ruby, JavaScript, SQL, GraphQL, Go, PHP, TypeScript, Python, CSS, HTML, HTML5, Swift, Elixir, C#, Objective-C, Solidity, DYNAMO, Java, CoffeeScript, Snowflake, C++
Frameworks
Ruby on Rails (RoR), React Native, Flutter, Next.js, Tailwind CSS, NestJS, Serverless Framework, Ant Design, Redux, Unity, Django, Express.js, JSON Web Tokens (JWT), Vuetify, CodeIgniter, Material UI, Ionic, Laravel, Jest, Phaser.io, Cypress, Bootstrap, Angular
Paradigms
Test-driven Development (TDD), Application Architecture, Cross-platform, Mobile Development, Mobile App Design, Scalable Application, Unit Testing, DevOps, Agile, Microservices, HIPAA Compliance, Search Engine Optimization (SEO)
Platforms
Amazon Web Services (AWS), iOS, Mobile, WordPress, Firebase, Twilio, LocalStack, Blockchain, AWS Lambda, Docker, Google Cloud Platform (GCP), Android, Shopify, Kubernetes, Heroku, Ethereum, AWS Elastic Beanstalk, Visual Studio Code (VS Code), Azure, Webflow, Vercel
Storage
PostgreSQL, Redis, MySQL, Amazon DynamoDB, Amazon S3 (AWS S3), Amazon Aurora, Elasticsearch, Google Cloud Storage, MongoDB, Azure SQL
Other
Back-end, APIs, Web Development, Full-stack, Architecture, Software Architecture, Lambda Functions, Google Tag Manager, Google Analytics 4 (GA4), MERN Stack, Integration, Front-end, Product Management, API Integration, Mobile Apps, Startups, Software Design, FastAPI, Technical Leadership, Fintech, A/B Testing, Analytics, User Experience (UX), User Interface (UI), Mobile App Development, Full-stack Development, Page Speed Optimization, Web3, Decentralized Finance (DeFi), Minimum Viable Product (MVP), Technical Architecture, Web Usability, Customer Relationship Management (CRM), Mobile UX, Progressive Web Applications (PWAs), Web Applications, Open Source, Authentication, Artificial Intelligence (AI), Apollo, Ethereum Smart Contracts, Smart Contracts, Non-fungible Tokens (NFT), Localization, CI/CD Pipelines, Server-side Rendering (SSR), Leadership, Mobile First, CTO, Bots, Cryptocurrency, Crypto, Health, Single Sign-on (SSO), Payment APIs, Payment Gateways, PayPal, Third-party APIs, Plugins, Web Scraping, Cryptography, PCI Compliance, Algorithms, OAuth, WebSockets, Serverless, mParticle, Cosmos, TypeORM, User Authentication, Ruby Gems, Business Administration, Finance, No-code Development, eCommerce
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