# Charles Y.

> Software Engineer at Ecosystems

Location: New York City Metropolitan Area, United States
Profile: https://flows.cv/charlesy

Software engineer with nearly 10 years of frontend web development experience. Successfully built React applications that satisfy the WCAG accessibility standard and designed RESTful APIs using Java and SQL. Interested in web accessibility, design systems, and overanalyzing Vim configs.

## Work Experience
### Software Engineer @ Ecosystems.io
Jan 2024 – Present

### Software Development Engineer @ Amazon
Jan 2023 – Jan 2024
Hired as part of a dedicated web accessibility team for Amazon QuickSight, a business intelligence solution with 100,000+ customers including the NFL, Siemens, and Volvo. Our efforts secured a successful WCAG 2.1 (level AA) conformance report from third-party auditors. Some of my achievements and responsibilities included:

• Resolved key issues raised by external accessibility auditors, This ranged from simpler tasks like providing proper ARIA attributes to more complex projects such as building a focus management framework to improve keyboard navigation

• I independently conducted 3 accessibility audits and led the remediation by documenting the gaps, coordinating development with product owners, and implementing the necessary fixes

• Refactored/added React components in QuickSight's design system, which often involved working with custom widgets that were much more complex and feature-rich than the example implementations provided by the ARIA Authoring Practices Guide (APG). In addition to ensuring their compliance with WCAG, I reduced the risk of regressions and saved development time by simplifying their APIs, refining TypeScript typings, and automating error-prone tasks

• Ensured the longevity of our accessibility work by focusing on systematic improvements. I authored documentation regarding best practices, pitfalls in official specs and the design system, and suggestions for future improvement. I also added new utilities, proposed infrastructure upgrades, and increased test coverage

### Frontend Software Engineer @ Turing's Craft
Jan 2014 – Jan 2021
Served as the primary frontend engineer at Turing's Craft. I built the majority of the frontend, including the React rewrite of their flagship product CodeLab and its legacy jQuery version. Some other responsibilities and achievements included:

• Built 6 supplemental React applications including a CodeLab embed that increased customer adoption by integrating with 6 learning management systems and satisfying 94% of WCAG 2.1 (level AA)
• Authored a library of 100+ React components that prioritized WCAG compliance and accelerated development by standardizing essential widgets
• Implemented a Redux-based WYSIWYG XML editor, the backbone of CodeLab’s content management system, that could perform multi-select, drag and drop, undo/redo, filtering, and CRUD operations
• Developed an exercise framework with backend engineers that achieved up to a 500% boost in customer productivity by automating the creation of new homework problems
• Improved system reliability by building a Node.js service that tracked client-side errors, introducing testing infrastructure with Mocha and Chai, and designing REST API endpoints that paid off technical debt from a legacy JSP backend

### Intern @ Turing's Craft
Jan 2013 – Jan 2014
• Delivered interface improvements and bug fixes that led to a successful UI freeze for a product licensing agreement with Pearson and the deprecation of a legacy Flash client
• Built an analytics tool with jQuery that allowed instructors to easily measure student performance by visualizing submission statistics for hundreds of exercises
• Wrote regression tests with Selenium that ensured the quality of features critical to CodeLab's mission of improving learning outcomes


## Education
### Bachelor of Science (B.S.) in Computer Science
Brooklyn College
Jan 2010 – Jan 2014


## Contact & Social
- LinkedIn: https://linkedin.com/in/charlie-yao

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Source: https://flows.cv/charlesy
JSON Resume: https://flows.cv/charlesy/resume.json
Last updated: 2026-04-01