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

Castleton Tower is a boutique consulting firm founded by executives who have built and led quantitative research, data science, and technology teams at top-tier hedge funds and asset managers. We work with investment management firms (asset allocators, asset managers, hedge funds, family offices, and RIAs) helping them modernize their data infrastructure and build AI-ready foundations. We're looking for smart, motivated, high-agency people with similar backgrounds in either data engineering or investing. We have postings up on job boards, but if you email me a resume and 2 sentences you wrote on why you'd be a good fit, I will guarantee it gets looked at.

AI transformation firm shipping production AI systems for mid-market enterprises in regulated and technical domains — finance, energy, industrials, healthcare. We do not stop at PowerPoint AI strategy. We ship working systems alongside our clients' engineering teams. Small teams, deep expertise, real autonomy on real work.

Category Labs (formerly known as Monad Labs) is a team of systems engineers and researchers on a mission to design and build at the frontier of decentralized technology. We strive to design and build step-function improvements over existing blockchain solutions. After recently raising $225M in series A funding, led by Paradigm, we are growing our team.

Cathmere is a seed-stage startup revolutionizing how capital flows to emerging markets through our innovative fintech platform.

Cemit is a data intelligence company with ambitions to lead a digital transformation of the railway industry globally. As a scale-up supported by top-tier investors, we are a dynamic and customer-centric organization with R&D at the core of our DNA. Our platform collects data from trains or tracks and uses machine learning and analytics to provide real-time insight into the health of the trains and tracks to drastically improve maintenance efficiency and rail uptime. Together we are leading an intelligent shift that will increase the reliability, affordability, and efficiency of rail transportation, enabling a greener future.

Develop software to help the US Army solve pressing, tactical issues using a modern tech stack.

Census invented Reverse ETL and is now bringing it to development teams everywhere via their Embedded product. They deliver intuitive, fast, and rock-solid APIs that allow teams to integrate their data with dozens of warehouses and hundreds of SaaS applications.

Censys is the source for Internet Intelligence, conducting daily internet surveys to provide actionable data for identifying risks, researching emerging internet threats, and making the internet safer.