Biometric Technology at the Borders of Citizenship 323 population density and decreases with population size: the bigger the population, the harder to establish meaningful connection, but the higher its density, the higher the chances that said connection can concretise nonetheless. These considerations bear momentous consequences for theorising about the feasibility and convenience of enabling large-scale introducer-based onboarding options. Forthcoming onboardees are not the only class of potentially “underground” actors: introducers might well be so, too. Think about, for instance, taxi companies in South Africa: because of their job and the ties with local communities around the country, some drivers could well serve as introducers for digital onboarding, but because they themselves work in the informal economy (Genesis Analytics 2022, 11–12) and fear governmental auditing into the way they conduct their business, they would never come forward to serve as introducers unless the State pre-emptively stipulates relevant guarantees or tax amnesties – the latter would, however, apply only retroactively, and only to drivers up to a certain point in time, thus they might not prove as fitting the category’s interests as a whole. Similar limitations are acknowledged in the implementation of other digital technologies as well, including digital financial services – which would enhance inclusion, but are not trusted by informal workers who prefer cash-based transactions (Sharma and Díaz Andrade 2024, 9). To capture the introducer’s function, I shall not neglect some deeper sociological implications of its recruitment and deployment, that rest with collective fears and the public order. One question border officials are often displeased about, and that has a bearing towards the very role of the introducer, concerns whether ethnic selfidentification reduces or weakens national self-identification, with corollary quandaries around the impact of such disclosures and identifications on social stability and the security of border areas (e.g. Luo 2022, 93). For our purposes here, one consequent question might be: should the introducer promise to the “introducees” that their self-identification will be prioritised and featured into their identity documents? In the positive, could different technical standards be envisioned to cater for the different expectations and customs of different ethnic components being registered? This is a paradigmatic illustration of how nationality as cultural stratification matters even when one, legally speaking, is only deploying technology to address citizenship (or more generally identity) issues. In any case, the introducer should behave as neutrally as possible. In particular, it should not be perceived as “siding” with the authorities to “assess” one’s worthiness for citizenship and identity recording. In legal sociology literature, “good citizenship” is defined as all those attributes that mark one’s good standing towards a country’s rulers (Sköld 2019, 218); it comes as exceedingly problematic whenever legal citizenship is offered in conjunction with “credit score” systems linked to one’s