B-OISU-moon-2-5-x-upgrade-is-blocked-upstream-by-its-embedded-proto
The repo pins moon = "2.4.3" in .prototools. 2.5.x was evaluated and does
not run here: moon 2.5.3 embeds proto 0.55.4, and the current Bun toolchain
plugin requires proto >= 0.60.0-alpha.0, so initialisation fails with
proto::tool::minimum_version_requirement: Bun plugin … requires proto 0.60.0-alpha.0, found 0.55.4
Reproduced under a real proto home, a standalone proto 0.61.1 on PATH, a fresh PROTO_HOME, and MOON_TOOLCHAIN_FORCE_GLOBALS. The embedded runtime is what decides, so none of those help — this is upstream, not configuration.
Revisit when moonrepo ships a build embedding proto >= 0.60. Until then 2.4.3 is correct and the pin should not move.
Separately worth carrying forward whenever the version does move: 2.4.3 has a
--downstream deep bug where an affected-projects run expands to every task of
every downstream project, ignoring both the target list and a
--query "projectLayer!=application" filter. CI works around it by querying the
project set first and then running scoped to it (see .github/workflows/ci.yml).
Re-test whether the workaround is still needed on the version that lands.