🍰 CAKE paper's out, the design bet: the compiler isn't a fixed black box the agent calls — it's part of the harness, and it's under evolution too. CAKE didn't inherit existing abstraction layer. no tile/layout abstractions: the vocabulary was distilled by agents from a corpus of production kernels. every pattern the agent couldn't express pushed new primitives into the IR, and the analyses to keep them checkable. every barrier/layout bug that kept coming back became a verifier rule. none of this can be designed up front. the IR has to co-evolve with the kernels, and the workload tells you what's missing, the corpus tells you if the fix broke anything. the best language for an agent is the one that tells you what's illegal, what's slow, and which decision might made it faster.