Performance & Efficiency rules

Load fonts via next/font (google or local) and apply on html/body; avoid runtime <link> to fonts that cause FOUT/CLS.

For third-party scripts, use <Script> with an appropriate strategy and onLoad callbacks. Avoid dangerouslySetInnerHTML for scripts.

Combine ActiveRecord relations with `or` instead of materializing arrays or concatenating results.

For large sets, prefer a periodic sweep job rather than spawning one job/timer per item.

Extract repeated inline collections to unmodifiable static constants.

Use String#replace for literal substrings instead of replaceAll unless regex is required.

Use StringBuilder for many concatenations in loops or when building large strings.

Prefer Struct (or value objects) over OpenStruct for performance and type clarity.

Check for cases of string concatenation using +. Template literals improve readability and are less error-prone.

Ensure that resources such as streams or file handlers are managed using try-with-resources to avoid leaks.