Promptfoo · Acquired by OpenAI, March 2026

Promptfoo, founded in 2024 by Ian Webster and Michael D'Angelo, built a category-defining platform for AI security and evaluation. The platform enables developers and enterprises to systematically red-team AI systems against prompt injections, jailbreaks, data leaks, tool misuse, and compliance violations — turning adversarial testing into a routine part of the AI development lifecycle. By 2026, Promptfoo's tools were used by more than 25% of the Fortune 500, with 350,000 developers having used the open-source project and 130,000 active monthly.

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Brightmind worked with Promptfoo in an advisory capacity, drawing on the firm's operator background in cybersecurity and its bench of CISO relationships across enterprise buyers. On March 9, 2026, OpenAI announced its acquisition of Promptfoo to integrate the platform into OpenAI Frontier — its enterprise platform for building and operating AI agents launched in February 2026. Promptfoo's open-source project will continue under OpenAI's stewardship.

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The Promptfoo outcome reflects the thesis Brightmind invests behind: AI evaluation, red-teaming, and compliance tooling have become foundational infrastructure for enterprise AI deployment, not optional add-ons. Vijil, a Brightmind Series A lead, is building in this same category for the agent-trust layer.

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