# Legacy upgrade compatibility The 1.x host-directory detector, vendored-copy synchronizer, and destructive Git replacement blocks were duplicated installation infrastructure. GStack 2 delegates skill placement and updates to the standard Agent Skills installer and manages the optional shared runtime atomically. - Update selected skills with `npx skills add time-attack/gstack/skills` using the user's existing project/global choice. Never infer or enroll a host. - Upgrade a complete local runtime package with `gstack upgrade --source --version `. - Roll back the runtime with `gstack upgrade --rollback`. - Run `gstack doctor` after either operation. - Do not reset, delete, move, or rewrite a host skill directory. Do not infer Context.dev choice or consent. This compatibility module contains no specialist judgment; release readiness and rollback judgment remain in the preserved ship modules. ## Upstream judgment port: PR #679 [Match the user language](https://github.com/garrytan/gstack/pull/679) ### User-language rule Write questions, progress updates, reports, and artifacts in the language used by the user. Source material, code identifiers, commands, and quotations may remain in their original language when translating them would reduce accuracy.