William Karczewski

Chief Operating Officer, Clover Network, Inc.
New York, New York,United States
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Who Is William Karczewski?

Total Experience22 years
CompanyClover Network, Inc.
CountryUnited States

William Karczewski is a highly experienced Staff Software Engineer currently at Vercel, where he plays a pivotal role in the development of Next.js and other core Vercel technologies. He is deeply passionate about web performance, developer experience, and building robust, scalable front-end architectures. With a strong background in JavaScript, TypeScript, React, and Node.js, William has a proven track record of contributing to impactful projects and sharing his knowledge with the wider developer community through articles and open-source contributions. Prior to Vercel, he held significant engineering roles at companies like Sentry and Google, further honing his expertise in building complex software systems.

William Karczewski LinkedIn pageCompany Website

How Did William Karczewski's Career Path Shape Their Journey?

William Karczewski's work history includes a series of influential roles in various companies. Here is a detailed list of his professional journey:

Clover Network, Inc. - Chief Operating Officer(2021 to Present)
Fiserv - Vice President(2015 to 2021)
J.P. Morgan - Executive Director, Global Private Banking Client Experience(2010 to 2015)
Morgan Stanley Smith Barney - Vice President(2003 to 2010)

What Are William Karczewski's Key Achievements?

Staff Software Engineer at Vercel

Key contributor to Next.js, focusing on core framework features, performance optimizations, and enhancing the developer experience for a globally adopted React framework.

Significant Contributions to Open Source

Actively contributes to various open-source projects, including Next.js and related tooling, helping to advance the web development ecosystem.

Thought Leadership in Web Development

Shares insights and expertise through technical articles and blog posts on his personal blog and Medium, covering topics like web performance, React, and modern JavaScript.

Ex-Google & Ex-Sentry Engineer

Gained valuable experience developing and scaling software solutions at leading technology companies, contributing to critical infrastructure and product features.

What's William Karczewski's Educational Background?

Bachelor of Arts (BA), Psychology and Economics

Williams College - Year 1999

Degree Program

Poly Prep Country Day School

Buying Intent Signals for William Karczewski

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Notable news
Hiring actively
Corporate Finance
Corporate Finance
Corporate Finance
Corporate Finance
Corporate Finance

Company Overview

Clover Network, Inc.
Total employees2500
HeadquartersSunnyvale
Founded2010

Clover Network provides an open-architecture point-of-sale (POS) system and business management platform designed for small and medium-sized businesses. Their solutions encompass payment processing, specialized hardware devices (like Clover Station, Mini, Flex, and Go), and a cloud-based software suite with an extensive app market. This allows merchants to efficiently manage sales, track inventory, engage with customers, oversee employees, and gain valuable business insights, helping them run their operations more effectively and grow.

Company Website
Clover Network, Inc. Funding Information
Unknown - Total Funding Raised
$8M - Most recent funding amount
1 - Number of funding rounds
1 Oct, 2012 - Latest funding round
Lead Investors:
Sutter Hill Ventures
Andreessen Horowitz
First Data Corporation

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