ArtofBlockchain

Difficulty - Medium

Total Plays - 8

Allowed Time - 10 sec

Best time - 2.492

What does REVERT preserve that INVALID does not?

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Explanation:
REVERT allows returning structured revert data back to the caller, which improves debugging and interface guarantees. INVALID terminates execution with no return payload. This distinction is crucial for protocols relying on bubble-up error messaging.

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Difficulty - Medium

Total Plays - 7

Allowed Time - 10 sec

Best time - 3.912

Which op is used for external code size?

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Explanation:
EXTCODESIZE checks if the target has code deployed. It helps detect contracts vs EOAs in validation logic

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Difficulty - Medium

Total Plays - 8

Allowed Time - 10 sec

Best time - 10

Why are multi-step writes risky?

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Explanation:
Multi-step operations can leave the contract in a partially updated state if execution halts. Attackers exploit these interim states to bypass checks.

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Difficulty - Medium

Total Plays - 6

Allowed Time - 10 sec

Best time - 5.375

Why is SELFDESTRUCT dangerous in proxies?

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Explanation:
If the implementation contract is self-destructed, proxies break permanently or redirect unexpectedly. This creates bricked contracts and undefined behavior

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Difficulty - Medium

Total Plays - 9

Allowed Time - 10 sec

Best time - 10

What does RETURNDATASIZE prevent?

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Explanation:
RETURNDATASIZE ensures the caller knows exactly how many bytes were returned. It prevents incorrect assumptions and truncation bugs during low-level calls.

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Shubhada Pande
@ShubhadaJP • Jul 9, 2026

Jul 9, 2026
2.4K

Proof-Based Hiring in Web3: A Founder’s Guide to Evaluating GitHub, Tests, Smart Contracts, and Audit Claims

Updated for 2026 Web3 hiring signals: this guide focuses on how founders, recruiters, and hiring managers can evaluate blockchain candidates through visible proof before relying on interviews alone. While hiring,...

Like 3 Replies 1
ChainPenLilly
@ChainPenLilly • Nov 28, 2025

Nov 28, 2025
298

How do you rebuild clarity in a smart contract team when owner-driven docs slip, handovers get messy, and weekly alignment stops working?

I’m a mid-level smart contract developer in a small DeFi team, and I’m noticing a pattern: every time deadlines get tight, clarity collapses. Owner-driven docs start slipping, handovers get messy,...

Like 0 Replies 1
smith taylor
@kmBguOK • Nov 28, 2025

Nov 28, 2025
668

Final Year, 2 Internships Done — How Do I Get My First Full-Time Blockchain Developer Role?

I’m in my final year of college and just wrapped up two internships, but I still don’t have a full-time blockchain developer offer. Both internships were with small startups where...

Like 5 Replies 4
Web3WandererAva
@Web3Wanderer • Jul 9, 2026

Jul 9, 2026
2.7K

Blockchain Engineer vs. Developer: What’s the Actual Difference?

What is the actual difference between a blockchain engineer and a blockchain developer? I just graduated in CS and I’m applying for Web3 roles, but the titles are a total...

Like 8 Replies 10
Difficulty - Medium

Total Plays - 14

Allowed Time - 10 sec

Best time - 1.846

Why is storing large arrays on-chain discouraged?

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Explanation:
Storage is the most expensive resource in the EVM. Large arrays result in high operational cost and poor long-term scalability.

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Difficulty - Medium

Total Plays - 14

Allowed Time - 10 sec

Best time - 0.675

Why is using block.timestamp in fairness-critical logic dangerous?

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Explanation:
Miners can adjust timestamps within a reasonable range, enabling subtle manipulation. This can affect auctions, lotteries, and reward systems

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Damon Whitney
@CareerSensei • Nov 26, 2025

Nov 26, 2025
647

Burned Out as a Blockchain Developer in Dubai — Is Switching to DevRel Actually a Better Long-Term Career Move?

I’m honestly feeling burned out after 3+ years working as a blockchain developer in Dubai. Long hours, late-night deployments, nonstop tech changes… it’s draining. I still care about Web3, but...

Like 5 Replies 6
Amanda Smith
@AmandaS • Nov 26, 2025

Nov 26, 2025
2.2K

I Know Solidity, but Interviews Now Feel Like Security Exams — What Advanced Questions Should I Really Prepare For?

I’ve been writing Solidity for a few years now — mostly production contracts, not tutorials — but the interviews I’m getting lately feel completely different. They used to be about...

Like 14 Replies 6
Difficulty - Medium

Total Plays - 8

Allowed Time - 10 sec

Best time - 3.010

5. Why is delegatecall risky?

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Explanation:
delegatecall executes callee code in the caller’s storage context, leading to storage collisions and privilege escalation. This is a key attack vector in proxy contracts.

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Difficulty - Medium

Total Plays - 7

Allowed Time - 10 sec

Best time - 10

4. Which opcode is responsible for dynamic memory expansion cost?

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Explanation:
MSTORE triggers memory expansion when writing to higher memory slots. Memory grows quadratically, so developers must understand how loops and large arrays impact gas.

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Difficulty - Medium

Total Plays - 9

Allowed Time - 10 sec

Best time - 4.033

What happens if a constructor of a deployed contract reverts?

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Explanation:
If the constructor reverts, the entire deployment fails and no contract is created. This prevents partially-initialized smart contracts from being pushed on-chain

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Arif
@ofh3VYy • Nov 25, 2025

Nov 25, 2025
371

🚀 I Want to Become a StarkNet/Cairo Auditor — Here’s My Starting Point & I’d Love a Roadmap

I’m transitioning my focus toward StarkNet and Cairo security auditing and would appreciate guidance from anyone experienced in the ecosystem.What I know so far:• Solidity development• Hardhat, Foundry, and advanced...

Like 3 Replies 4
Difficulty - Medium

Total Plays - 6

Allowed Time - 10 sec

Best time - 4.975

1. What does EXTCODEHASH primarily help detect?

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Explanation:
EXTCODEHASH returns the hash of a contract’s deployed bytecode, allowing detection of code changes or empty accounts. Auditors use it to verify contract identity and defend against unexpected contract replacement patterns

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Difficulty - Medium

Total Plays - 9

Allowed Time - 10 sec

Best time - 5.082

What is the main security benefit of using immutable variables?

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Explanation:
immutable variables are stored directly in bytecode, not in storage, reducing runtime gas and preventing accidental overwrites. It is a common optimization technique in gas-efficient contract design.

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Victor Anderson
@victor-anderson • Nov 23, 2025

Nov 23, 2025
1.8K

Solidity Gas Optimization in Interviews: Why Juniors Fail the Question and What Seniors Actually Look For

I realized recently that I’ve been approaching “gas optimization” totally wrong in interviews. Every time the question comes up, I start dumping the usual lines — avoid storage writes, use...

Like 2 Replies 4