<!--
title: Modern shell syntax
domain: data-systems
topic: Code Style
language: Yaml
source: neondatabase/neon
updated: 2025-05-23
url: https://awesomereviewers.com/reviewers/neon-modern-shell-syntax/
-->

Prefer double brackets (`[[ ]]`) over single brackets (`[ ]`) in shell scripts for improved functionality and consistency. While double brackets don't strictly require quotes around variables, maintaining consistent quoting practice is recommended even with double brackets:

```bash
# Preferred style
if [[ "$variable" == "value" ]]; then
    # code
fi

# Instead of
if [ $variable == "value" ]; then
    # code
fi
```

This practice enhances readability and offers protection if scripts are later modified to use single brackets or embedded in contexts with stricter requirements.