Pattern: Large Language Ports Are Now Viable When Gated by Conformance Tests + Adversarial Review

Simon Willison·high signal

Jarred Sumner describes porting Bun from Zig to Rust in 11 days (July 8) by running coding agents against a conformance test suite with an adversarial review loop, echoing Geoffrey Litt's "understand to participate" (July 2) argument that you must retain enough comprehension to steer. The emerging pattern for big migrations isn't 'let the agent rewrite it' — it's building the oracle (conformance tests) and the skeptic (adversarial reviewer) first, then letting agents grind against them.