Who Is Jack Sharkey, the Whop Cofounder and CTO?

Jack Sharkey is a cofounder and the chief technology officer (CTO) of Whop, an online marketplace for digital software, subscriptions, courses, and communities.

Who Jack Sharkey Is

Sharkey joined Steven Schwartz and Cameron Zoub as the developer at Whop's founding and built the Ruby on Rails platform and API that Whop's AI integrations now run on.

Whop's Jack Sharkey is a different person from the 1930s boxer of the same name. Fortune named him Whop's third cofounder in June 2024, and his Rails World 2025 speaker bio says he is passionate about developer experience and scaling Rails.

• Current role: Cofounder and Chief Technology Officer (CTO) of Whop.
• Company: Whop (founded 2021, headquartered at the Domino Sugar Refinery in Brooklyn, New York).
• Cofounders: Steven Schwartz (Chief Executive Officer) and Cameron Zoub (Chief Growth Officer).
• Known for: His Rails World 2025 talk "The $1B Rails Startup: Scaling from 0 to Unicorn in Four Years".

Early Programming and Pre-Whop Projects

Sharkey said in his Rails World 2025 talk that he started as a sneaker botter in 2014. He said he learned programming in high school, building websites and iOS apps that never passed 100 users.

In the same talk, he said he built Shark Trivia, an HQ Trivia-style iOS app, as part of appealing a University of Texas admission rejection. The decision was overturned and he attended UT.

He said a COVID-era startup, his first Rails project, ran 9 months and reached about $7K MRR before failing.

Founding Whop and the Node Versus Rails Decision

At Rails World 2025, Sharkey said that in 2020 Steven Schwartz pushed to build their startup on Rails while he argued for Node. He said he came from a Node.js / Express background before Rails.

Sharkey said they argued for a few hours before he agreed, and he later called it "one of the worst arguments I've ever made."

Whop launched in March 2021, per CNBC Make It. Sharkey said Whop's first version was a Rails app using a ThemeForest Bootstrap template, hosted on Heroku. He said he was still in college while building early Whop, working nights and weekends. He said Whop sold $25,000 of software in its first month and $100,000 in its second, with roughly 50 to 100 users.

Database Migrations and Infrastructure Evolution

In his Rails World 2025 talk, Sharkey said Whop's first scaling problem came in 2022 from "flash drops" on 2x Heroku dynos. He said a contractor found via Codementor fixed it by removing N+1 queries.

He said that during a 2022 Friday-night outage, cofounder Cameron Zoub ("Cam") suggested sending an Uber to the off-duty contractor's house, and the site was back up about 10 minutes later.

Sharkey said Whop ran on four databases in four years: Heroku Postgres, self-hosted Postgres on EC2, Aurora on Amazon Web Services, and PlanetScale MySQL. Sharkey described the migration to self-hosted Postgres on EC2 as probably the worst technical decision Whop ever made. He said Whop migrated from Postgres to MySQL on PlanetScale with zero downtime over about two months in early 2025.

Sharkey said at Rails World 2025 that Whop built chat four times over about a year, and real-time notifications three times over about six weeks.

Rails World 2025 and the RailsConf 2024 Keynote

At Rails World 2025, Sharkey gave the talk "The $1B Rails Startup: Scaling from 0 to Unicorn in Four Years," which he said was his first ever talk. The talk abstract on the Rails World 2025 schedule says Whop handles 150k RPM and runs chat, notifications, payments, and live streaming on a Rails monolith. The full 25-minute presentation is hosted on the Ruby on Rails YouTube channel.

Sharkey said Whop had 15 engineers in 2025, with only three to four working on Rails. He told attendees he would be the first customer of anything they started in the next 30 days.

Whop was also featured as a case study in Irina Nazarova's RailsConf 2024 keynote, "Startups on Rails in 2024," available on Speaker Deck. Her keynote slides quote Sharkey: "We could ship every feature our customers asked for, because Rails enabled us to build sooo fast" and "I don't understand why more startups are not choosing Rails."

Whop's Developer Tools and AI Integrations

Whop operates an API and a dedicated command-line interface (CLI) that its integrations run on. The Whop API guide covers the API and CLI in detail.

Whop has API partnerships with Replit, Poke, Cal.com and others. In late August 2026, SpaceXAI named Whop as Grok's first full-stack business connector.

On September 2, 2026, Whop was listed in the Cursor Marketplace under "Payments" and went live as a plugin in Grok Bot. The Whop AI guide covers the Grok and Cursor integrations. Sharkey's GitHub account, sharkey11 (created January 2016), lists company Whop and 17 public repos. One public repo, "swarm", is a Rust "Terminal dashboard for managing multiple AI coding agents in parallel".

Whop Capital Rounds and Valuation History

In July 2023, Whop closed a $17 million Series A led by Insight Partners, with participation from Peter Thiel, Zinal Growth, Justin Mateen, Justin Kan, The Chainsmokers, and Kevin O'Leary. AlleyWatch listed Whop's total funding at that point as $18 million. At that stage, Whop documented over $110 million in cumulative transaction volume.

In June 2024, Fortune reported that Whop raised a Series B of more than $50 million led by Bain Capital Ventures. Whop then had 4 million people a month using it and a workforce of 50. On February 25, 2026, Tether made a $200 million investment in Whop, valuing it at $1.6 billion, as covered by PYMNTS. Under the deal, Whop will use Tether's Wallet Development Kit for on-chain settlement.

By June 2026, Fortune reported Whop had raised about $272 million over five years. Whop then had around 22 million users and supported around $4 billion in annual commerce.

On October 21, 2026, Bloomberg Law reported that Whop secured a $205 million funding round led by Sequoia Capital, elevating Whop's valuation to $5.1 billion. Tech Funding News reported that Shopify's venture arm also invested and that former Sequoia leader Doug Leone joins Whop's board. Whop's own announcement put the Series D at $200 million, per Pulse 2.0.

• July 2023 Series A: Raised $17 million led by Insight Partners; cumulative funding reached $18 million.
• June 2024 Series B: Secured $50 million (reported by Fortune as over $50 million) led by Bain Capital Ventures.
• February 2026 Tether Round: Tether invested $200 million, establishing a $1.6 billion valuation.
• October 2026 Series D: Raised $205 million (reported by Whop as $200 million) led by Sequoia Capital at a $5.1 billion valuation.

The Whop Founding Team and Executive Roles

Steven Schwartz is cofounder and CEO of Whop, which moved its headquarters to the Domino Sugar Refinery in Williamsburg, Brooklyn, in 2024.

Cameron Zoub is a Whop cofounder and its chief growth officer. Zoub and Schwartz met as middle schoolers in a Facebook group about sneaker reselling and wrote sneaker bots as teenagers. Sharkey joined them as the software developer when Whop was founded.