ArtofBlockchain

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Difficulty - Medium

Total Plays - 10

Allowed Time - 10 sec

Best time - 2.358

Why is PUSH0 useful in gas optimization?

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Explanation:
PUSH0 provides a zero literal without consuming calldata or memory. This reduces bytecode size and simplifies stack management. It's extremely helpful in tight loops and assembly-heavy contracts.

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Difficulty - Medium

Total Plays - 7

Allowed Time - 10 sec

Best time - 10

What does “state shadowing” indicate in inheritance?

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Explanation:
State shadowing happens when a derived contract redeclares a state variable with the same name as a parent. This creates storage misalignment and unexpected slot overwrites. Auditors treat this as a major upgradeability and correctness risk.

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Difficulty - Medium

Total Plays - 7

Allowed Time - 10 sec

Best time - 2.234

Why is calldata preferred for router functions?

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Explanation:
Calldata avoids copying user inputs into memory, significantly reducing gas usage for large payloads. Router contracts receive untrusted inputs, so avoiding memory expansion is both cheaper and safer. This is why AMMs and DEX routers heavily rely on calldata

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Difficulty - Medium

Total Plays - 6

Allowed Time - 10 sec

Best time - 3.026

Why do auditors flag “silent reverts”?

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Explanation:
Silent reverts hide failure reasons, making debugging and validation difficult. They also open the door for inconsistent execution paths

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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 • Aug 23, 2026

Aug 23, 2026
2.5K

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, most founders review code thoroughly, as the wrong hire can cost massively. In the Web3...

Like 4 Replies 1
ChainPenLilly
@ChainPenLilly • Nov 28, 2025

Nov 28, 2025
335

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
708

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 • Aug 5, 2026

Aug 5, 2026
2.9K

Blockchain Developer vs. Engineer: Salary, Tech Stack & Career

Moderator Note: While job ads use these terms interchangeably, Web3 teams distinguish Application-Layer Developers (Solidity, React, dApps) from Protocol-Layer Engineers (Rust, Go, EVM internals, ZK rollups). Let's explore the key...

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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
684

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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