Bash Safety & Best Practices

When writing or reviewing bash scripts, apply the rules below. For the complete catalog of rules with detailed examples, see reference.md.

Sources: BashPitfalls, Shellharden.

Rule 0: Run ShellCheck

Before any manual review, run static analysis:

shellcheck -o all script.sh

-o all enables every optional check (including those not on by default). Fix all errors and warnings before proceeding. ShellCheck catches the majority of the pitfalls listed here automatically.