[PERF] Implement Gas-Optimized Contract Existence Check in Yul

[mijinummi]

Labels: medium-difficulty, yul, security, gasguard
Difficulty: Medium
Module: contracts/utils/

---

🧠 Concept

Replace high-level .code.length checks with a dedicated Yul helper that evaluates extcodesize directly.

⚠️ Problem

High-level contract checks in Solidity create additional stack management instructions before executing the extcodesize opcode.

📁 Implementation Scope

• contracts/utils/CodeCheckLib.sol
• test/utils/CodeCheckLib.test.ts

🛠️ Requirements

1. Implement isContract(address target) returns (bool result) using inline Yul:
   result := gt(extcodesize(target), 0)
2. Ensure function is declared internal pure.

🎯 Acceptance Criteria

• Provides fast, gas-efficient verification of deployment status for target addresses.
• Operates cleanly across local unit tests and testnets.

[BestBisong]

@BestBisong has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would like to work on this issue pls assign it to me

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[devwums]

@devwums has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello, I'm interested in taking this issue on.

I have hands-on experience with backend development, databases, and API design, as well as frontend work with React and modern CSS. I write tested, maintainable code and enjoy contributing to open source projects.

I've gone through the details of this issue and I'm confident I can deliver a clean, well-tested solution that fits the codebase.

Looking forward to contributing — please assign this issue to me.

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[Caneryy]

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Hello! Can I work on this issue please?

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[drips-wave]

Congratulations, @devwums! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox!

@devwums's PR #675 was approved and merged by @mijinummi.

🏆 @devwums: You earned 40 FoxPoints for this contribution! Your current tier: Builder (1,092 total points). Track your full progress on GrantFox.

👏 Great work, @devwums! Keep contributing to MDTechLabs.

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