Two ways to run multiple Claude Code subscriptions (personal + work) on one machine, side-by-side, without a re-login every time you switch.
Use long-lived OAuth tokens + direnv. The keychain-swap approach originally in this gist has a subtle bug: Anthropic's short-lived OAuth credentials rotate on every refresh, so a snapshot you saved to disk goes stale within hours. Symptom — "please log in" every time you return to the other profile. Long-lived tokens (claude setup-token, 1-year TTL, no rotation) sidestep the problem entirely.