Harden Bash

Gate

Read the script and every caller before changing it. Determine whether it is executed or sourced, which inputs cross trust boundaries, which privileges and side effects it has, and which shell actually parses it.

Contracts

• Choose Bash or POSIX sh explicitly. Never mix their language or runtime contracts.
• Control expansions and preserve argument boundaries.
• Build commands as argv, never as executable strings.
• Make expected and unexpected failures visible with useful status and context.
• Keep secrets out of argv, logs, permissive temporary files, and tracing.
• Validate destructive scope before mutation.
• Add no abstraction or operational feature without a demonstrated contract.

Workflow