A water utility engineer has personal editor preferences and the team has mandatory coding standards. How should they be separated?

Personal editor preferences and mandatory team standards must live at different layers. A water utility engineer should keep personal preferences in user-level settings and mandatory team standards in the project repository so keybindings stay private while safety and coding rules ship to everyone who clocks in.

Why the correct option works: user-level settings apply only to that user and are not shared; project repo config distributes mandatory standards. Separating raincoat-level personal taste from plant safety manuals prevents both forced personalization of teammates and accidental privatization of legal/retention rules.

Why the other three fail by concept: committing personal keybindings into project CLAUDE.md for every teammate pollutes shared standards with one person’s editor habits. Storing mandatory standards only in one engineer’s user CLAUDE.md hides them from the rest of the utility. Mixing personal aliases and legal retention rules in the same unscoped chat loses hierarchy, auditability, and persistence.

Exam caveat: ask “must every clone obey this?”—if yes, project repo; if only you care, user-level. Operational check: move personal prefs to user settings, keep retention and coding standards in project config, clone as a second user, and verify mandatory rules load without the first engineer’s keybindings.