Quilter raises $25M Series B from Index Ventures to automate circuit board design
Oct 8, 2025 with Sergiy Nesterenko
Key Points
- Quilter closes $25M Series B led by Index Ventures to automate PCB circuit board design, competing as a horizontal tool across aerospace, automotive, and consumer electronics.
- Large enterprises are the primary driver of adoption, not startups, because they run multiple designs simultaneously and face exponentially higher costs from production delays.
- Quilter operates at the design layer, not manufacturing; PCB fabrication remains distributed across hundreds of US fabs and thousands in China, with offshore still dominating volume production.
Summary
Quilter, a circuit board design automation startup, has closed a $25M Series B led by Index Ventures. The company has 25 employees and is run by CEO and founder Serenko, who spent five years designing avionics for Falcon 9 and Falcon Heavy at SpaceX before starting Quilter roughly five years ago.
The core product automates PCB layout and design, positioning itself as a horizontal tool that works across industries — aerospace, consumer electronics, automotive — because the underlying physics (electromagnetics, thermodynamics) and materials are consistent enough that vertical-specific tooling isn't necessary. Serenko draws an explicit parallel to Cursor: one tool for any software engineer, regardless of what they're building.
Customer pull
The primary value proposition is speed to market. Electronics engineers prototype and iterate in much the same way software engineers do — testing small pieces before committing to production — and compressing that cycle is where Quilter wins. Counterintuitively, the strongest demand is coming from large enterprises rather than startups. Serenko attributes this to volume: big companies run far more designs simultaneously, and the cost of a single lost day is orders of magnitude higher than it is for an early-stage team.
Manufacturing context
Quilter is a design-layer company, not a manufacturing one, and Serenko draws a sharp distinction between PCB fabrication and chip fabrication. The US has hundreds of PCB fabs; China has thousands. Domestic production is used primarily for fast-turnaround prototypes — boards needed within one to three days. Volume production still flows offshore, where costs are dramatically lower. Serenko sees room for more US investment in PCB manufacturing capacity but frames it as a separate problem from what Quilter is solving.