ArtofBlockchain

Difficulty - Medium

Total Plays - 26

Allowed Time - 10 sec

Best time - 1.582 sec

Which opcode returns remaining gas?

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Explanation:
GASLEFT returns the amount of gas remaining in the current execution context. It is commonly used for gas-aware logic and debugging.

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Difficulty - Medium

Total Plays - 23

Allowed Time - 10 sec

Best time - 3.422

Which type consumes exactly one storage slot regardless of value?

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Explanation:
bytes32 always occupies a full 32-byte storage slot. Smaller types may be packed together, but bytes32 always stands alone.

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Shubhada Pande
@ShubhadaJP • Mar 27, 2026

Mar 27, 2026

447

Proof-Based Hiring in Web3: Hiring Signals, Recruiter Screening, JD Proof Lines, and Shortlist Quality

Proof-based hiring in Web3 is not just about asking whether someone has “worked in blockchain.” Strong hiring decisions come from visible proof: shipped work, explainable decisions, GitHub trail, testing depth,...

Like 4 Replies 2
Difficulty - Medium

Total Plays - 20

Allowed Time - 10 sec

Best time - 1.200

Why does storage write order matter for structs?

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Explanation:
Solidity packs struct variables tightly into storage slots based on declaration order. Reordering fields can change slot boundaries and break upgrade compatibility.

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Shubhada Pande
@ShubhadaJP • Apr 4, 2026

Apr 4, 2026

303

Zero-Knowledge Cryptography Hub for Smart Contract Engineers

Zero-knowledge cryptography gets talked about like a prestige topic, but in real teams and real interviews, the gap is usually simpler than that. Many candidates can name ZK terms. Fewer...

Like 4 Replies 1
Difficulty - Medium

Total Plays - 16

Allowed Time - 10 sec

Best time - 0.784

What determines the base slot of a mapping?

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Explanation:
The base slot of a mapping is derived using keccak256(key . slot). This hashing ensures unique storage locations per key without collisions.

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CryptoSagePriya
@CryptoSagePriya • Jan 1, 2026

Jan 1, 2026

352

I’m starting my first smart contract job next week and I’m honestly nervous — what actually matters during probation?

I’m starting my first smart contract job next week and honestly I’m nervous.Everyone keeps saying “probation decides everything” but no one really explains how.Some people say move fast. Some say...

Like 6 Replies 9
Difficulty - Medium

Total Plays - 13

Allowed Time - 10 sec

Best time - 5.093

Which operation causes storage slot re-packing?

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Explanation:
Changing variable types alters how Solidity packs them into storage slots. This can shift offsets and corrupt existing storage layouts in upgradeable contracts.

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Difficulty - Medium

Total Plays - 20

Allowed Time - 10 sec

Best time - 1.638

Which data location is read-only by default?

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Explanation:
Calldata is immutable and cannot be modified by the callee. This makes it gas-efficient and safe for external function inputs

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Difficulty - Medium

Total Plays - 19

Allowed Time - 10 sec

Best time - 1.548 sec

What happens to storage slots after contract self-destruct?

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Explanation:
Storage is not automatically wiped when a contract self-destructs. The data remains on-chain and can be accessed again if a contract is redeployed at the same address.

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Difficulty - Medium

Total Plays - 22

Allowed Time - 10 sec

Best time - 1.455

Why is bytes32 cheaper than string in storage?

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Explanation:
bytes32 has a fixed 32-byte size and fits into a single storage slot. string is dynamically sized and requires additional storage pointers and length metadata.

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Difficulty - Medium

Total Plays - 23

Allowed Time - 10 sec

Best time - 3.228

Which operation resets a dynamic array length to zero?

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Explanation:
Using delete on a dynamic array sets its length to zero. Storage slots may remain allocated but become inaccessible through the array.

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Difficulty - Medium

Total Plays - 19

Allowed Time - 10 sec

Best time - 3.454

What does delete do to a mapping entry?

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Explanation:
Deleting a mapping key resets its value to the default type value. The key itself still exists conceptually since mappings do not track keys.

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Difficulty - Medium

Total Plays - 18

Allowed Time - 10 sec

Best time - 1.444

Which data location persists across transactions?

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Explanation:
Storage persists on-chain across transactions and blocks. Memory and calldata are temporary and cleared after execution completes.

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Vijay B
@xDhgFi3 • Dec 31, 2025

Dec 31, 2025

213

How would you approach breaking into protocol development as a final-year Solidity dev?

Hi everyone,I’m a final-year student and have been involved in Web3 since 2021. I spent close to two years interning with startups and am comfortable with Solidity (writing, debugging, and...

Like 2 Replies 4
Sayali Bhandari
@SayaliB • Dec 30, 2025

Dec 30, 2025

2.1K

Stuck Between AI and Blockchain — Feels Like I Might Choose Wrong

I’m at a confusing point in my career and could use honest input from people who’ve been in the space longer.I’ve spent time learning blockchain basics and building small things,...

Like 5 Replies 4
Aditi R
@aGoKU4J • Dec 28, 2025

Dec 28, 2025

330

Clean code, but still rejected — what do juniors miss in take-home assignments?

I’m a junior developer and I keep running into the same problem. My take-home assignments usually work, the code is clean, but I still get rejected — often without any...

Like 3 Replies 4
Difficulty - Medium

Total Plays - 18

Allowed Time - 10 sec

Best time - 4.491

What happens if a public variable name conflicts with a function name?

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Explanation:
Public variables automatically generate getter functions. If a function shares the same name, the compiler prioritizes the variable-generated getter, shadowing the function definition.

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AshishS
@Web3SecurityPro • Dec 28, 2025

Dec 28, 2025

2.2K

What skills actually matter for UI/UX roles in NFT platforms and decentralized identity?

Looking to get into UI/UX design for blockchain and metaverse projects—what’s the real deal with hiring right now?For those already working on NFT platforms, virtual asset tools, or decentralized ID...

Like 10 Replies 7
Difficulty - Medium

Total Plays - 18

Allowed Time - 10 sec

Best time - 3.013 sec

Which keyword prevents further inheritance of a contract?

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Explanation:
Solidity does not support a final or sealed keyword for contracts. Any contract can be inherited unless architectural constraints are enforced manually.

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