Braintrust
Braintrust builds an evaluation and monitoring platform for companies shipping AI features. It provides tools for testing, benchmarking, and improving LLM behavior in production. “Teams at Notion, Stripe, Zapier, Vercel, and Ramp use Braintrust to compare models, test prompts, and catch regressions — turning production data into better AI with every release.”
WorkOS
WorkOS builds tools and services for developers to help them implement authentication, identity, authorization, and overall enterprise readiness. They’ve raised $100m and have customers including OpenAI, Cursor, Perplexity, and hundreds of others.