CLAUDE_CODE_NEW_INIT

Updated October 13, 2026 by Alex Sorokoletov

CLAUDE_CODE_NEW_INIT is a Claude Code environment variable: Toggles a refactored initialization path that reduces startup memory usage. The changelog explicitly highlights "~18MB" savings across all scenarios, which is a significant reduction for a Node.js CLI tool. Added between v2.1.77 and v2.1.79 and still present in v2.1.294. It is listed in the official reference.

Status	Present in v2.1.294
Added	Added between v2.1.77 and v2.1.79
Category	Other
Official docs	Listed

How to set it

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

export CLAUDE_CODE_NEW_INIT=<value>
claude

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

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

Release notes that mention it

Related variables

CLAUDE_CODE_GROWTHBOOK_KICK_FROM_INIT
CLAUDE_CODE_HOLD_REPORT_PARK_AT_INIT
ANTHROPIC_BETAS: Comma-separated beta feature headers.
ANTHROPIC_CUSTOM_HEADERS: Custom HTTP headers (newline-separated Key: Value).
ANTHROPIC_FEDERATION_RULE_ID
ANTHROPIC_ORGANIZATION_ID
ANTHROPIC_WORKSPACE_ID
BETA_TRACING_ENDPOINT: Custom endpoint for beta tracing.

Frequently asked questions

What does CLAUDE_CODE_NEW_INIT do?

Toggles a refactored initialization path that reduces startup memory usage. The changelog explicitly highlights "~18MB" savings across all scenarios, which is a significant reduction for a Node.js CLI tool.

Which Claude Code version has CLAUDE_CODE_NEW_INIT?

Added between v2.1.77 and v2.1.79 and still present in v2.1.294.

How do I set CLAUDE_CODE_NEW_INIT?

Export it before starting Claude Code (export CLAUDE_CODE_NEW_INIT=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.