每日新聞摘要

Scaling Kotlin adoption requires aligning migration strategy with application lifecycles and organizational goals. Urs Peter recommends three lifecycle-driven approaches: leave end-of-life apps in Java, default new systems to Kotlin, and perform pragmatic, feature-driven migration for active applications. Java-to-Kotlin conversions include four paths: complete rewrite for small codebases; IDE auto-conversion with manual refinement (improved by nullability annotations like jspecify); AI-assisted conversion when robust tests and careful prompts exist; and rule-based, deterministic transformations for organization-wide, large-scale migrations as practiced at Meta and Uber. Each approach has trade-offs: auto-conversion yields non-idiomatic Kotlin needing manual cleanup; AI can be more idiomatic but requires extensive tests and human review; large-scale automation must manage social impact and PR overload. Beyond tooling, success depends on training, coding standards, and building team expertise to reach idiomatic Kotlin and sustained value.

在组织内规模化采用 Kotlin 需要将迁移策略与应用生命周期与业务目标对齐。作者建议：计划退役的系统保持 Java，绿地项目默认使用 Kotlin，对正在运行的应用采用与新功能结合的渐进迁移策略。Java 到 Kotlin 的转换有四种方法：适合小型项目的完整重写；适用于中型项目的 IntelliJ 自动转换并人工精修（可用 jspecify 改善可空性）；适用于有完备测试的大中型代码库的 AI 辅助转换；以及面向全组织的大规模、基于规则的系统化转换（如 Meta、Uber 的做法）。每种方式各有权衡，成功还依赖培训、编码标准、测试覆盖与人为复审来保障长期价值。

Amper 0.9.0 ships the first preview of its extensibility system, enabling local plugins that define custom tasks implemented in Kotlin and registered via plugin.yaml under the new jvm/amper-plugin product type. The preview supports automatic task wiring, inferred dependencies, classpath inputs, generated outputs, and task avoidance; publishing and sharing plugins, templates, and additional task-authoring conveniences are planned. Performance improvements include caching the dependency graph to reduce IDE import and sync time and an optional incremental Java compiler (enabled via settings.java.compileIncrementally) to recompile only changed code within modules. New ergonomics let projects keep a Maven-like directory layout for jvm/app and jvm/lib modules, place a single libs.versions.toml at the project root, and benefit from IDE additions such as auto-sync, richer sync details, main-class completion, catalog quick-fixes, Amper YAML color settings, and updated default tool versions. Try the update with ./amper update and share feedback on Slack or YouTrack.

Amper 0.9.0 带来首个可扩展性预览：可以创建 jvm/amper-plugin 类型的模块，在 Kotlin 中实现自定义任务并通过 plugin.yaml 注册输入输出，工具会推断任务依赖并默认启用任务避开（task avoidance），支持类路径输入以及将输出注册为生成的源码或资源。未来将支持发布/共享插件、随插件携带的配置模板、减少单模块任务样板、任务作者常用服务和更多 IDE 快修。其他改进包括缓存依赖图以提升 IDE 导入/同步性能、可选的增量 Java 编译、允许为 jvm/app 与 jvm/lib 保留 Maven-like 布局、在项目根放置 libs.versions.toml、自动同步、主类补全、目录版本快速修复、Amper YAML 颜色设置以及默认工具版本更新。使用 ./amper update 更新并在 Slack 或 YouTrack 提交反馈。