William Lubelski | Résumé

Product-minded frontend engineer building thoughtful products and the systems that make them easier to develop, maintain, and evolve.

Professional Experience

Mercury

September 2024–Present

Senior Frontend Engineer Remote / SF Bay Area

Product engineer for Spend Management.

Rebuilt a legacy form library with TypeScript and React hooks, using advanced types to preserve backwards compatibility.

Toast

October 2022–August 2024

Staff Frontend Engineer Remote / SF Bay Area

Led a team to improve Shift Management search performance, reducing page load times for larger customers from multiple minutes to 500 ms.
Led the navigation and branding overhaul for the Payroll product.
Built frontend infrastructure for localization, wizard workflows, type-safe reactive localStorage, and client-side navigation alongside legacy server-rendered pages.

Carta

2021–2022

Senior Developer II, Frontend Remote / SF Bay Area

Re-architected data fetching and the frontend of TotalComp.
Designed and built the frontend for the HRIS integration system.
Supported a junior engineer leading the Total Rewards frontend project; advocated for and adopted Carta’s micro-frontend system.

Peach Finance

July 2020–May 2021

Senior Frontend Developer Remote / SF Bay Area

Built the customer-facing payments and account management portal.
Designed a system to embed the customer portal in the admin portal for smoother support interactions.

Worklete

April 2019–February 2020

Senior Frontend Developer San Francisco, California

Led the transition from a white-label CMS prototype to an in-house web application, prioritizing simple, maintainable architecture.
Mentored junior engineers through pair programming and cross-team collaboration.

EverTrue

March 2015–April 2019

Frontend Developer Boston, Massachusetts

Built features for data-rich CRM and nonprofit fundraising applications using React and Backbone.
Designed and built a Flux-based state management library, then helped transition the application to modern React practices.
Mentored junior frontend developers.

Earlier experience includes frontend development at Kitewheel (2014), UX at SoftArtisans (2011–2012), and mechanical engineering at Bicon Dental Implants (2008–2011, 2012–2014).

Education

University at Buffalo (SUNY)

B.S. Aerospace Engineering; B.A. Mathematics

Bentley University

Coursework in Human Factors in Information Design, including user research, testing and assessment, and measuring user experience.

General Assembly

Product Management evening course, Boston, Massachusetts

Technical Practice

TypeScript, JavaScript, React, and CSS. Type-safe library design, state management, data fetching, performance, and legacy-system integration. Experience with CSS-in-JS, styled-components, LESS, and PostCSS; a grounding in UX and human factors.