feat(resolved-deps): one answer for "which version is this dependency" - #34
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`deps_exports` carries only what a dependency explicitly declared, and its
contract said absence means "fall back to convention". That sentence is what
authorised four independent answers to one question — and with two versions
of a package installed they disagree, producing a binary whose INTERP comes
from one payload and whose RUNPATH from another. It segfaults before `main`
and the error names a GLIBC_PRIVATE symbol, saying nothing about versions.
`ResolvedDep` is the record `deps_exports` could not be: TOTAL. Every runtime
dep appears, declared or not, carrying the version the resolver settled on,
the absolute payload directory, the libdirs (convention-filled by the writer
rather than re-derived by each reader), and WHY that version — "plan",
"pinned-active", "only-installed". Without the last field there is no
answering "why is it 2.39 on this machine".
Three consumers change:
* `pkginfo.dep_install_dir` becomes a lookup. The scan and the xvm-active
fallbacks remain for callers with no install context, and warn when they
fire inside one, so a guess is never silent.
* `elfpatch.closure_lib_paths` LOSES its re-derivation branch — the one
that took a dep's name, resolved it again, and probed {lib64, lib}. That
was the second answerer. The convention did not disappear; it moved to
the single place entitled to apply it.
* `resolved_dep()` is exposed for hooks that need the record directly.
Probed with `type(...) == "table"`, never truthiness: an unknown _RUNTIME
field is nil, but the same test against a module proxy is true everywhere —
a trap this repo has fallen into twice.
Read side first, deliberately. xlings 2026.8.5.3 adds the writer and an
assertion that a provider's loader and libdir come from one payload; shipping
that first would make the assertion fire on clients that cannot send the
record yet.
Design: xlings/.agents/docs/2026-08-05-dependency-resolution-single-source.md
Sunrisepeak
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Aug 5, 2026
resolved_deps: a total record of what the resolver decided for every runtime dependency, so "which version is this dep" stops having four independent answers. elfpatch's re-derivation branch is deleted rather than fixed. See openxlings/libxpkg#34.
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deps_exportscarries only what a dep declared, and its contract said absence means fall back to convention. That sentence authorised four independent answers to one question; with two versions of a package installed they disagree, and the product is a binary whose INTERP and RUNPATH come from different payloads — segfault beforemain, error naming a GLIBC_PRIVATE symbol.ResolvedDepis total: every runtime dep, declared or not, with the resolved version, the payload directory, convention-filled libdirs, and why that version.closure_lib_pathsloses its re-derivation branch — the second answerer. The convention moved to the one place entitled to apply it.dep_install_dirbecomes a lookup that warns when it has to guess.Read side first: xlings 2026.8.5.3 adds the writer and the same-source assertion, and shipping that first would make it fire on clients that cannot send the record.
Design:
.agents/docs/2026-08-05-dependency-resolution-single-source.mdin xlings.