Implement subscription contract formal verification

[Smartdevs17]

Implement subscription contract formal verification

Description

Context: Smart contracts handle financial assets requiring formal verification for correctness.

Current Limitation: No formal verification exists.

Expected Outcome: Implement formal verification using Certora or similar.

Acceptance Criteria

• Define formal specifications for core contract functions
• Implement verification rules for: balance, authorization, state transitions
• Add invariant checking
• Document verification results
• Implement continuous verification in CI

Technical Scope

Files Likely Affected:

• contracts/subscription/specs/ - Formal specifications
• contracts/subscription/certora/ - Verification rules

[Itodo-S]

@Itodo-S has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

please let me work on this i can handle it.

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[mimijuwonlo-commits]

@mimijuwonlo-commits has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

can i fix this?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @mimijuwonlo-commits to this issue.

[drips-wave]

Congratulations, @mimijuwonlo-commits! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

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[drips-wave]

This issue has been completed by @mimijuwonlo-commits as part of the Stellar Wave Program's 4th Wave 🥳

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