The official Valve SDK zip (provided by Cyd), trimmed to what the gated build consumes: public/ (steam_api.h, ISteamNetworkingSockets, ISteamMatchmaking, the full public header set) + redistributable_bin/ (steam_api.lib/.dll all platforms) + Readme. glmgr/steamworksexample/ tools dropped. Used ONLY under -DBT_STEAM=ON (step 4); the pod and plain glass builds never reference it. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>