Andres Quan-Littow
Verified Expert in Engineering
Full-stack Developer
Salt Lake City, UT, United States
Toptal member since March 14, 2023
Andrés is a full-stack, front-end-oriented React engineer with a passion for software architecture. He constantly seeks ways to expand his knowledge and skills and believes that solutions must be planned, started, and implemented correctly. Andrés specializes in React and focuses mainly on responsive, mobile-first design.
Portfolio
Experience
- SQL - 7 years
- REST - 7 years
- JavaScript - 6 years
- Scrum - 5 years
- React - 5 years
- TypeScript - 5 years
- Python 3 - 3 years
- Rust - 2 years
Preferred Environment
SQL, TypeScript, React, CSS, HTML, Rust, Domain-driven Design (DDD), Claude, Data Engineering, Back-end Development
The most amazing...
...thing I've done is create, design, and work on web pages and web-based systems to improve the productivity of various enterprises.
Work Experience
React Front-end Engineer
Databricks - Main
- Implemented solutions to the pre-existing Account Login and Setup flow.
- Created and implemented the Add-ons selection functionality for Workspaces.
- Actively used several tools, including AI and design, to better manage simple tasks, such as bug fixes, decreasing time-to-ship.
React and ASP.NET Engineer
SumerSports, LLC - Main
- Participated in the development of a complex feature requiring the rewriting and extension of a drag-and-drop library with concurrency features.
- Developed, led, and optimized several state-based features with event-based communication for ease of use in the application.
- Led and suggested changes to the project structure to ease the development of new features, components, and services in both Next.js 14 and 15, increasing productivity and implementing a standard.
- Adapted, learned, and implemented features in the back end using .NET 8 (originally, I was only supposed to be a front-end developer).
- Optimized several APIs, hooks, and states in the application's front end, increasing performance significantly.
- Implemented components based on D3.js for increased performance in a data-intensive application, rather than taking the easy (but slow) way with state. Components are still easy to manage.
- Implemented graphs and other information-based components based on D3.js.
- Centralized, normalized, and fixed the database data, enforcing rules based on the business logic in .NET, increasing the ease of use of several different APIs.
- Implemented browser APIs for the customization of URLs based on the state of the application, separating concerns correctly for ease of change.
Full-stack Developer
MolyWorks Materials
- Developed an application using state-of-the-art frameworks on both the front and back end.
- Planned live services and architectures for intensive workloads.
- Managed team members and a project as the lead developer.
- Created a workflow system that allows for the management of resources based on the enterprise's specific needs.
- Used and mastered different technologies, including (but not limited to) NestJS, Next.js (React), TypeORM, Prisma, etc.
Technical Screener
Toptal
- Developed applications utilizing Ruby, Python, and JavaScript/TypeScript.
- Worked on multi-team projects regarding new initiatives for productivity.
- Built personally published projects that modified webpages to increase productivity for other screeners.
- Evaluated different coding styles and focused on scalability and clean code.
Back-end Developer and Team Lead
BDG & Walmart
- Developed systems to enable reporting inside the system regarding dashboards.
- Created cron jobs and microservices to aid with the creation of new architectures inside Walmart.
- Led and distributed new applications to help with Walmart's payment and discount systems in Latin America.
- Managed and did code reviews for big projects done in .NET.
Full-stack Developer
Esserman
- Managed and created massive database migrations to a new system.
- Designed and implemented a new system while being outsourced to the Guatemala Regional University (Universidad Regional de Guatemala).
- Managed several systems, specifically those based on JavaScript.
- Developed and implemented different parts of mobile applications using React and Vue Native.
Back-end Developer
Universidad Regional de Guatemala
- Helped develop an entire system to communicate with one of Guatemala's most prominent banks.
- Tracked and managed information in data-intensive applications with Laravel.
- Managed and debugged pre-existing applications with no documentation, working with legacy systems.
Organizer and Salesman
Grupo Macrina
- Developed the infrastructure for different products.
- Facilitated the buy-and-sell of different sections and departments.
- Created and managed the main database to maintain the quality of the product and keep transactions as fast as possible.
Experience
Payment System
The payment system had to follow certain security measures that were imposed by the bank to manage its own API. Like every bank, it had to be able to create transactions, change them, or reverse them. The system was done to receive payments through the university's portal.
React-based Vite Application
Twitch Jobs Project
Homepage for a Software Company
Education
Master's Degree in Business Intelligence and Analytics in Data Science
Universidad del Valle de Guatemala - Guatemala City, Guatemala
Bachelor's Degree in Computer Science
Universidad del Valle de Guatemala - Guatemala City, Guatemala
Skills
Libraries/APIs
React, Node.js, REST APIs, Vue, Python API, Telegram Bot API, Solid, Slack API, Framer Motion, Pandas, Asyncio, SQLAlchemy, Zod, React DnD, Apollo Client, D3.js, Lodash, React Testing Library
Tools
Git, GitHub, Figma, Webpack, Slack, Expo, Prisma, Visual Studio, Cloudera, Premiere Pro 2020, Tableau, Power BI Desktop, Apache ZooKeeper, AWS SDK, React Apollo, Claude, Claude Code
Languages
TypeScript, JavaScript, GraphQL, SQL, Python, Python 3, CSS, HTML, HTML5, Elixir, C++, C, C#, Ruby, Bash, Bash Script, PHP, Java, Rust, R, Sass, Scala
Paradigms
Back-end Architecture, REST, Scrum, UI Design, Object-relational Mapping (ORM), UX Design
Storage
JSON, MySQL, Databases, Amazon DynamoDB, MongoDB, PostgreSQL, Neo4j, Microsoft SQL Server, HDFS, MSSQLCE, Apache Hive, Redis Cache, Redis
Frameworks
NestJS, React Native, Angular, .NET, Bootstrap, Material UI, Laravel, Express.js, Tailwind CSS, Next.js, Remix, Jest, Django, Ruby on Rails (RoR), .NET Core, Spark, Hadoop, Svelte, Cypress
Platforms
Linux, Docker, AWS Lambda, Amazon EC2, Amazon Web Services (AWS), Firebase, Mobile, Blockchain, Windows Server, Alteryx, Databricks, Azure, Jupyter Notebook, RStudio, Apache Kafka, Patreon
Other
Back-end Development, Back-end, Front-end, Algorithms, Full-stack, APIs, Web Hosting, User Experience (UX), User Interface (UI), Webhooks, Design, Web UI, Server-side Rendering (SSR), Amazon RDS, API Connectors, TypeORM, Front-end Development, Containers, Telegram Bots, Full-stack Development, Game Development, Game Design, Content Management Systems (CMS), Strapi, Vite, Chakra UI, UI Animation, CI/CD Pipelines, API Integration, Online Payments, Payment APIs, Web Scraping, TSOA, Platform as a Service (PaaS), SaaS, Infrastructure as a Service (IaaS), Data Science, Web3, Storybook, SvelteKit, Single-page Applications (SPAs), MERN Stack, Zustand, ESLint, Apollo, Data Grids, Drag & Drop, Styled-components, Domain-driven Design (DDD), Data Engineering
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