Core principles of contemporary constitutionalism, if adequately translated and re-articulated, can help guide the development of social media. Digital constitutionalism is the ideological movement advocating for this process of ‘constitutionalisation’ of the social media environment. The rule of law principle plays a crucial role in this context. It can be used as a litmus test to identify areas in need of intervention. Platform law, the so-called lex digitalis, cannot aspire to surge from its current status of arbitrarily imposed ‘feudal law’ if it does not achieve a sufficient level of codification. This effort must go in tandem with a proceduralisation of content moderation practices. However, this chapter argues that both a full codification of the lex digitalis and a meaningful incorporation of procedural rules presuppose a solid assessment of the values that should govern global content moderation. The decision of whether to stick to a specific international human rights law standard or adopt a platform’s own values represents a dilemma. Yet, the progressive judicialisation of the social media environment, accompanied by the ‘maieutic’ role of national courts, bodes well in terms of resolution of this normative conundrum.