A stroll through venture history: Convertible notes were a useful hack for startups and VCs because the fixed cost of taking equity capital versus debt was very high for seed rounds. Spending $30k on legal fees for a $1M round is absurd. The problem was that notes were still debt, which came with all the usual accouterments (maturity, interest, etc.). A seed-stage startup is either making it to an A round or going to zero; having to service debt is pointless. The original YC SAFE preserved the speed of a convertible note but removed the debt-like components that didn’t apply to startups. This was great. But those SAFEs used pre-money caps, which introduced a pile of conditional logic into cap tables during fundraising. We used to give pre-money conversion exercises to applicants. I’d bet there are tens—maybe hundreds—of millions of dollars’ worth of misallocated or misconverted shares sitting in startup cap tables. This brings us to the modern post-money YC SAFE: it’s as fast as a note, has no debt elements, and provides an intuitive, deterministic conversion for follow-on rounds. It’s an excellent product.