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MGS4005: environmental drift

A generated output changed when you regenerated it, but its declared inputs are byte-identical to what is committed, and you are running a dev build. The committed form was produced by the pinned release (the compatibility contract: CI regenerates with a checksum-verified release binary), so a dev build rendering it differently is version or toolchain skew, not a change you made.

[MGS4005] generated output drifted but its declared inputs are unchanged; the committed
form is produced by the pinned release and you are running a dev build (v0.1.0-5-gabc123)
- not your change, do not commit

Why

magus treats a generated file as a pure function of its declared inputs plus the generator and tool versions. When the inputs are unchanged, the only remaining variable is the generator/tool version. A local HEAD build, a locally installed formatter (prettier, a badge renderer), or any tool whose version differs from the pinned release can render the same inputs to different bytes - the classic markdown-emphasis case (*x* vs _x_). That difference is real, but it is not your change, and committing it would just re-introduce the same skew against the next machine.

Resolution

Do not commit the drift. Discard it (git checkout -- <paths>) and move on. If the files genuinely need regenerating for a real reason, regenerate with the pinned release (the version CI uses) so the bytes match the contract, not with a local dev build.

If you believe the inputs really did change, see MGS4006 (stale generated output) - that is the code you would get instead.

race diagnosticsLanding page for MGS4xxx race condition diagnostics emitted by the magus race detector across static, watch, and replay modes. MGS1020: output owned by two targetsFires when two targets in the same project declare the same output glob, so whichever runs last wins and the other target's drift gate fails on the next run. magus stdlibReference for every magus stdlib module - fs, os, http, json, yaml, crypto, and the rest of the magusfile API surface. knowledge-graph diagnosticsLanding page for MGS7xxx diagnostics that flag ambiguities the knowledge-graph extractor hits while building the deterministic graph, such as a buzz import that resolves to no file or a doc that cites an unregistered diagnostic code.
MGS4005driftgenerateddeterminismenvironmentversion skewtoolchain
Last updated (b022d75e)
Glossary

CI

An ordinary magusfile-defined target you compose yourself with magus\needs - magus does not hardcode its stages. Magus.RunCI treats it specially only in that it strips the rw charm, it is the anchor magus affected ci keys off, and a selected scope with no project declaring it is a load error rather than a silent no-op. See targets.

Conventions

Placeholders

Angle brackets mark a value you replace with your own - never type the brackets:

magus run <target>
magus completion <shell>    # e.g. bash, zsh, fish

<target>, <path>, <shell>, <name> and the like are stand-ins, not literal text.