Sarah Buchner, a former carpenter in Austria, founded Trunk Tools after a worksite fatality inspired her to prioritize safety. She later earned a Ph.D. in data science, recognizing fragmented construction data as a solvable problem. In 2021, she launched Trunk Tools at Stanford, integrating AI to analyze unstructured project data. The company now uses AI agents to streamline contracts, drawings, and workflows, addressing construction’s complexity. Trunk Tools has raised $70 million, with revenue growing fourfold in 2024 and a $325 million valuation after a 2025 Series B. Buchner, a solo founder, leverages her industry expertise to navigate construction’s tech-wary culture.

Trunk Tools’ AI agents process 3 million to 4 million pages of documentation per site, flagging issues like cost overruns or safety hazards. For instance, the system identified a $4 million cost increase from a project change, preventing unnecessary expenses. Another agent provided real-time safety instructions when a worker was exposed to chemicals. This ability to connect fragmented data across workflows is critical in construction, where changes have cascading effects. Buchner’s background allows her to empathize with clients’ operational challenges, blending technical insight with industry practicality.

The startup now employs 100 people, offering training and change-management services alongside software. Despite initial fundraising struggles due to her non-traditional background, Trunk Tools gained traction by addressing concrete pain points. Buchner emphasizes solving real problems over fitting conventional business models. Her Ph.D. and operational experience position her as a unique founder in an industry slow to adopt tech. Trunk Tools’ focus on AI agents—now numbering over 10—reflects rapid innovation, though scaling sales teams remains a challenge. The company serves general contractors, subcontractors, and project owners, expanding its impact in a sector historically resistant to digital transformation.