Ian Webster

@iwebst

building @Promptfoo (LLM security) + "curator of the world's largest digital dinosaur database"

Ian Webster
@iwebst
Mar 9
Promptfoo will be joining OpenAI. We’re staying open source and we’re going to keep supporting customers and users. We built Promptfoo to help devs test and secure AI apps. The results have been phenomenal: 350k+ developers, 25%+ of the Fortune 500, 23 people, ~2 years. AI
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Ian Webster
@iwebst
Feb 24
The OpenAI vs Anthropic enterprise narrative is skewed by sketchy data and VCs with agendas. Here's what we've seen in ~100 recent enterprise convos with actual builders. 71% of sampled cos have >$1B in revenue, 54% are public with over 10k employees
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Ian Webster
@iwebst
Jul 29, 2025
We’ve raised an $18.4M Series A led by @insightpartners, with participation from @a16z, to build the best security stack for AI applications. Promptfoo started a year ago as an open source project and is now the most widely adopted toolkit for reducing security, compliance, and
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Ian Webster
@iwebst
Sep 17, 2024
Anthropic has been quietly publishing top notch content on LLM fundamentals. Lots of great examples of using Promptfoo for evals in this new course!
Alex Albert
@alexalbert__
Sep 16, 2024
Our latest course on LLM prompt evaluations is out. Evals ensure your prompts are production-ready as you're able to quickly catch edge cases and zero in on exactly where your prompts need work. Let's walk through what the course covers:
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Ian Webster
@iwebst
Aug 30, 2024
Doing online support can be a drag, but sometimes you get gems like this
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