JetBrains open-sources KotlinLLM: the model writes persistent Kotlin at the call site.

Apache 2.0 IntelliJ plugin introducing "Smart macros" whose bodies are generated Kotlin source, regenerated only when the app hits runtime scenarios the existing code doesn't cover. Once generated, it's ordinary Kotlin: no plugin dependency, no inference latency, no per-call token cost. An adapted Spring Petclinic completed 24/24 scenarios after macro evolution with 100% hot-reload rate and ~1% runtime overhead; a GitHub Issue Radar hit ~0.89 recall across 30,000+ issues. The repo ships the committed generated sources so you can read what the model actually wrote. This is the right shape for a lot of "call an LLM at runtime" code that shouldn't be. (JetBrains)