CLAUDE_CODE_DIR_SYNC_OVERLAY

Updated October 14, 2026 by Alex Sorokoletov

CLAUDE_CODE_DIR_SYNC_OVERLAY is a Claude Code environment variable. Removed between v2.1.241 and v2.1.245, so current releases ignore it. It is not in the official reference.

Status	Removed between v2.1.241 and v2.1.245
Added	Added between v2.1.238 and v2.1.241
Category	Other
Official docs	Not listed

How to set it

For one session, export it in the shell that starts Claude Code:

export CLAUDE_CODE_DIR_SYNC_OVERLAY=<value>
claude

To apply it to every session, add it to the env object of a settings file:

// ~/.claude/settings.json
{
  "env": {
    "CLAUDE_CODE_DIR_SYNC_OVERLAY": "<value>"
  }
}

Release notes that mention it

claude-code-env-vars-v2-1-241

Related variables

CLAUDE_CODE_DIR_SYNC_ARCHIVE
CLAUDE_CODE_DIR_SYNC_ENGINE
CLAUDE_CODE_DIR_SYNC_FFWD
CLAUDE_CODE_DIR_SYNC_GIT
CLAUDE_CODE_PROJECT_DIR_NAME
CLAUDE_CONFIG_DIR: Custom config directory.
CLAUDE_JOB_DIR: Working directory for a background job, independent of the daemon's own cwd.
CLAUDE_PROJECT_DIR: Override project directory.

Frequently asked questions

Which Claude Code version has CLAUDE_CODE_DIR_SYNC_OVERLAY?

Removed between v2.1.241 and v2.1.245, so current releases ignore it.

How do I set CLAUDE_CODE_DIR_SYNC_OVERLAY?

Export it before starting Claude Code (export CLAUDE_CODE_DIR_SYNC_OVERLAY=value), or add it to the "env" object in ~/.claude/settings.json to apply it to every session.

All variables, searchable: Claude Code environment variables.