Rex
YC S26San Francisco, US · Founded 2026 · 2 employees · 2 known investors
Rex is an agentic finance platform that connects to existing enterprise financial systems and automates manual operational finance work like collections, reconciliation, and portal uploads using AI agents. The product is designed for finance teams at scaled technology companies seeking to delegate repetitive tasks while maintaining governance and audit compliance.
AI & Machine LearningEnterprise SoftwareFintechArtificial IntelligenceB2BEnterpriseUnited States of AmericaAmerica / Canada
Founders & leadership· Y Combinator alumni (S26)
Rex was founded in 2026 by Lewis Blackwood and Merlin Kafka.
LB
Lewis BlackwoodinCo-FounderHe was a founding engineer at Sequence, a venture-backed company, and cofounded Personably; earlier he was part of the initial team at GoCardless, a payments startup backed by Y Combinator, and studied economics at Cambridge University.
MK
Merlin Kafkain𝕏Co-founder & CEOMerlin spent four years as Chief Product Officer at Sequence, an order-to-cash platform, before founding Rex. He previously held a product management role at Tessian and studied Industrial Engineering at Cambridge and Product Design at Glasgow.
Investors · 2
In the news
Sotheby’s Big T. Rex Auction Raises Concerns Hype and Wealth Are Upending Science | WIREDwired.com · Jul 2026Frequently asked questions
- What does Rex do?
- Rex is an agentic finance platform that connects to existing enterprise financial systems and automates manual operational finance work like collections, reconciliation, and portal uploads using AI agents. The product is designed for finance teams at scaled technology companies seeking to delegate repetitive tasks while maintaining governance and audit compliance.
- Who founded Rex?
- Rex was founded by Lewis Blackwood, Merlin Kafka in 2026.
- Who are Rex's investors?
- Rex's investors include Y Combinator, Founders Fund.
- Where is Rex headquartered?
- Rex is headquartered in San Francisco, US.

