Communal Computing and Constitutional Governance

This technical brief asks how communal, embodied, locally modifiable computing could become a genuine computational public space rather than another private platform presented on a shared surface. Drawing on an author-supplied but presently unidentified Dynamicland transcript, it proposes a synthesis in which visible artifacts, shared physical context, local authorship, privacy by non-collection, governed admission, receipt waymarks, and portable constitutional representations support civic computation. The central contribution is architectural rather than empirical. Co-location is not common knowledge; visibility is not intelligibility; local control is not legitimate authority; physical possession is not automatically secure custody; and a receipt can become surveillance if it captures more than reconstruction requires. The brief therefore adds explicit primitives, a transition contract, universal-GSM/GMB placement, the complete realization funnel, a bounded pilot configuration, countermodels, failure modes, and publication decisions. It does not claim that a Dynamicland system, UGK integration, MCIR lowering path, civic deployment, or constitutional public space has been implemented or validated. Keywords: communal computing; constitutional computing; computational public space; Dynamicland; civic infrastructure; local-first systems; privacy by non-collection; receipts; governed admission; public artifacts; GMB; MCIR.