Cartesian Systems is a seed-stage MIT startup on a mission to map the physical world at unprecedented scale and precision. The company spun out of a lab at MIT in 2023 after 7 years of award-winning research and IP development in indoor mapping and localization. They have built their first product, deployed it with early customers, and are cashflow-positive.

Cash App provides banking services to millions of customers in the US. The Underwriting and Credit ML Engineering team builds the engineering systems and integrates ML solutions that are responsible for all credit decisions where Block advances funds or provides liquidity to consumers through Cash App and Afterpay. We support millions of customers through products like Cash App Borrow and Afterpay Buy Now Pay Later.

We build automated tools for PCB security verification.

Caspian is an early-stage venture backed startup focused on helping corporations manage their duty and tariff exposure, starting with duty drawback. The team has extensive experience in building enterprise products in the logistics space.

We're building trade software that actually works. Our first product is duty drawback. Every year $10B in potential refunds are left unclaimed. Data is unstructured, fragmented and trapped in legacy systems that don't talk to each other. We're helping companies organize and understand their trade data. Leveraging the wedge product, we intend to quickly grow beyond our initial product.

We're simplifying global trade compliance and helping importers navigate the trade environment, starting with duty drawback—a tax recovery process that puts cash back into importers' hands. Our platform transforms messy trade data into actionable insights, helping businesses recover from the estimated $10B in unclaimed refunds each year.

We’re building an AI-powered home manager: a proactive, chat-first system that helps homeowners stay ahead of bills, maintenance, documents, and expenses. We are backed by founders of Freshly ($1.5B), Kustomer ($1B), and more.

Cassidy is a no-code platform that allows businesses to build custom AI assistants that automate complex multi-step workflows. By connecting to a company’s knowledge (docs, wikis, calls, etc.) and leveraging major AI models, Cassidy aims to be the “AI colleague” for every team—helping them work 100x faster without heavy engineering overhead. We're well funded, growing incredibly fast and have an insane distribution advantage in a growing market.

Castle is a YC-backed Series A startup helping companies like Canva, Atlassian, and Rockstar Games fight fraud and abuse. They are building modern, AI-powered bot detection and abuse prevention tech, with a focus on real-time protection and behavioral intelligence.

Castleton Commodities is an energy fund with engineers in London, New York, and Houston.