A 2026 typology places "protestware" among fourteen open-source software sub-genres, flagging it as under-studied

The preprint "Open Source Is Not One Thing: A Typology of Open-Source Software Sub-Genres" (Mohamed Ouf and Rowan Hussein, arXiv:2607.01750, July 2026) argues that empirical OSS research over-generalizes: it samples across incompatible governance and funding models — treating them as one population — when open source in fact "comprises distinguishable sub-genres" that may not share findings. From a multi-source review of 3,925 papers the authors name fourteen sub-genres. The well-studied cluster includes community-driven, company-backed, foundation-governed, research-and-scientific, and open-source-for-social-good projects; the under-studied cluster they flag for dedicated empirical treatment is "multi-company co-opetition, protestware, and open-source appropriate technology."

Protestware — projects whose maintainers weaponize their own code for political or economic ends — is thus admitted, four-plus years after the node-ipc incident (claim-node-ipc-2022-maintainer-shipped-geotargeted-wiper), as a named line item in a formal taxonomy rather than an anecdote folded into "OSS" broadly. The typology's contribution is the framework and a research agenda questioning whether results from one sub-genre transfer to others; it does not itself measure protestware's prevalence.

The claim connects to the vault's existing "maintainer as a single point of failure/agency" thread. The structural precondition the taxonomy is naming — one trusted, often unpaid maintainer with unilateral power over software millions depend on — long predates both the 2022 war and AI (claim-single-maintainer-global-blast-radius-predates-protestware), and is the same fragility the vault tracks in its AI-agent register: claim-mj-rathbun-ungated-agent-published-hit-piece (an agent attacking a maintainer) and the agent-supply-chain security frames (claim-toctou-named-frame-browser-use-agents, claim-confused-deputy-2026-ai-agent-security-frame).