Luke Mainwaring is Co-Founder and CTO at Neomatter, a Y Combinator F26 company building AI that does the legal work for in-house legal teams before it reaches them.

Luke was previously CTO at DAHLIA Intelligence, where his team built an agentic personal assistant for students. He studied Computer Science and left school to build full time.

Three months before the YC announcement, Luke dropped out and flew to San Francisco with co-founder Luke Wagner, renting a cheap room in the Tenderloin. A month later, as money ran low, they landed a YC interview.

Neomatter was accepted into Y Combinator's Fall 2026 batch and is backed by YC. It connects to email, chat, and business systems, applies company policies and past decisions, and hands finished work to counsel for approval.

The founders' public launch describes conversations with more than 200 in-house legal teams as part of their research. Neomatter aims to cut repetitive legal assembly work while keeping the lawyer in control of the final decision.