Room 3.0 Migration Guide: From KAPT to KSP, Coroutines-First APIs, and KMP Web Support

--- title : " Room 3.0 Migration Guide: Drop KAPT, Embrace KSP and Coroutines-First APIs" published : true description : " A step-by-step workshop for migrating your Room database layer from KAPT to KSP-only codegen, adopting coroutines-first DAOs, and unlocking KMP web support." tags : kotlin, android, architecture, mobile canonical_url : https://blog.mvp-factory.com/room-3-0-migration-guide-kapt-to-ksp-coroutines-first-apis-kmp-web --- ## What We Will Build By the end of this tutorial, you will have migrated a Room 2.6.x project to Room 3.0 — swapping KAPT for KSP-only annotation processing, converting your DAOs to a coroutines-first API surface, and optionally wiring up the new KMP web target. I have run this migration on projects ranging from 50 to 500+ entities, and the pattern is the same every time. Let me walk you through it. ## Prerequisites - An existing Android project using Room 2.6.x with KAPT - Kotlin 1.9+ (you will bump to 2.0+ during migration) - Familiarity with Kotlin