Figma did almost everything a young public company is asked to do. Revenue rose 48% to $370.1m, beating estimates, its third straight quarter of speeding growth. It raised its full-year forecast. The stock fell about 16% after hours anyway.

The reason sits a few lines down the income statement. Building and running AI is expensive, and Figma’s spending has caught up with its selling. Research and development more than doubled to $167.3m. Total operating expenses nearly doubled to $426.9m. On a GAAP basis, the company swung to a $117.3m operating loss, Reuters reported.

The AI bill comes due

This was Figma’s first full quarter selling AI by the credit, and demand looked real. Net dollar retention held at 136%. More than 80% of its biggest customers now use AI credits every week. Over half already lean on the Figma agent it unveiled in June.

The trouble is that those features cost a fortune to build and to run. Adjusted operating margin fell to 10% from 16% in a single quarter. Figma also kept its full-year profit outlook flat while lifting the revenue line. In effect, every extra dollar of sales is being fed straight back into the product. Markets read a flat profit forecast beside a rising sales forecast as a warning.