Repository navigation
Add idempotency and duplicate-submission protection #626
Description
Priority: P0
Labels: backend, security, gameplay, priority: p0
Problem
A player could potentially submit the same answer multiple times because of:
- double clicking
- network retries
- browser refresh
- malicious requests
- frontend bugs
This becomes especially dangerous when XP or rewards are involved.
Requirements
Implement idempotency for challenge submissions.
Example:
submissionId
or:
Idempotency-Key
The backend must ensure the same submission cannot:
award XP twice
advance the session twice
create duplicate rewards
Acceptance Criteria
- Duplicate submissions are detected.
- XP cannot be duplicated.
- Reward eligibility cannot be duplicated.
- Session cannot advance twice.
- Tests cover repeated requests.
Activity
samkay-ops commentedon Aug 18, 2026
Hi team,
I'm applying to work on this issue.
I have strong experience with TypeScript, NestJS, and Soroban smart contracts. I will deliver clean, tested code following the acceptance criteria.
Ready to start immediately.
Best regards,
samkay-ops
TechBroAfrica commentedon Aug 18, 2026
Focused on building trust through consistent, meaningful contributions. I approach every issue with curiosity, attention to detail, and a commitment to delivering clean, maintainable, and well-tested solutions. Driven by impact, not just commits, I value clear communication, effective collaboration with maintainers, continuous learning, and delivering meaningful value to every project I contribute to.
arandomogg commentedon Aug 18, 2026
Hi, I’m interested in contributing to this issue. I’m a full-stack blockchain developer with experience in JavaScript/TypeScript and Web3 development. I’ve gone through the requirements and would be happy to work on the implementation, follow the project’s conventions, and submit a clean PR for review.
m-hajjo commentedon Aug 20, 2026
Hello Maintainer
i would love to handle this issue
grantfox-oss commentedon Aug 20, 2026
🦊 GrantFox — @m-hajjo has been assigned to this issue as part of the Third Campaign campaign!
Next steps:
Closes #626)Good luck! Track your progress on GrantFox.
grantfox-oss commentedon Aug 24, 2026
🎉 This issue has been marked as completed on GrantFox as part of the Third Campaign campaign!
@m-hajjo's PR #650 was approved and merged by @A6dulmalik.
🏆 @m-hajjo: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (694 total points). Track your full progress on GrantFox.
👏 Great work, @m-hajjo! Keep contributing to MindBlockLabs.