Changing Macs is normally straightforward. The surprising part is that signing into the same ChatGPT account does not necessarily recreate the local Codex working environment you had on the old machine.
Your repositories are only part of that environment. Local Codex conversations and state, project organization, custom skills, settings, Git worktrees, stashes, branches, and unfinished files can still live on the old Mac.
Here is the safe mental model and checklist I wish I had before my own move.
A migration is a one-time move from an old Mac to a new Mac. The old environment is the source; the new installation is the destination.
Sync means two Macs keep changing and must reconcile those changes repeatedly. That is a different and much harder problem. Blindly syncing internal Codex databases between two active installations can create conflicts or duplicate machine identity.
This guide covers migration.
For a complete developer-workspace move, inspect these categories separately: A Git push is valuable, but it does not automatically include uncommitted work, stashes that were never pushed, linked worktrees, local-only branches, or Codex’s local state.
Do not treat the entire ~/.codex directory as one portable blob.
The destination Mac should keep its own:
Copying machine-specific identity can make two physical Macs appear to Codex Remote Control as the same installation. Copying credentials also creates avoidable security risk.
Install ChatGPT/Codex on the new Mac, open it, and sign in once before replacing any portable state. That gives the destination its own authentication and installation identity to preserve.
After the move, check at least:
Only then should you consider the migration complete.
I ran into this problem myself, so I built Codex Migrate for this specific one-time Mac-to-Mac workflow.
It transfers portable Codex state and selected workspaces directly between your Macs over SSH. It inventories dependencies, stages the transfer, preserves the destination Mac’s authentication and installation identity, requires a verified destination backup before replacement, and supports /resume and recovery after interruption.
The paid app and free CLI use the same migration engine and safety checks. Payment covers the packaged, signed workflow and maintainer support—not stronger data protection.
Codex Migrate is an independent project. It is not affiliated with, supported by, or endorsed by OpenAI. Keep your old Mac and an independent backup until you have verified the result.