Why is there backend code in a frontend challenge?

In some frontend languages (most commonly JavaScript: React) you may come across challenges that include backend code.

This pattern of including backend code in frontend languages was intended to give more context to frontend developers and to show how vulnerabilities can affect the entire stack.

Note: Secure Code Warrior decided to move away from this pattern to remove confusion and increase specific applications of vulnerabilities in frontend code. All new content we create will follow this new pattern.
Some old challenges that contain backend code will be addressed on a per-challenge basis.

If you come across a challenge like this, please submit a bug or feedback whilst on the challenge screen and we will see what changes we can make right away.