ArtofBlockchain

Difficulty - Medium

Total Plays - 39

Allowed Time - 10 sec

Best time - 1.466

Which is a risk of using oracles?

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Explanation:
Centralized oracles can be a single point of failure. If they provide false data, contracts relying on them can be exploited.

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Difficulty - Medium

Total Plays - 42

Allowed Time - 10 sec

Best time - 1.573

Decentralized exchanges:

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Explanation:
Decentralized exchanges (DEXs) operate using smart contracts, which automatically execute trades without the need for intermediaries. This allows users to trade crypto directly from their wallets while maintaining control of their assets

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MakerInProgress
@MakerInProgress • May 10, 2026

May 10, 2026
2.7K

How can I transition from Web2 career to Web3 career for US startup developer roles (3 years full-stack)?

I’ve spent the last three years as a Web2 full-stack developer (React, Node, AWS) building and scaling production apps. Recently I keep searching the same thing: how can i transition...

Like 11 Replies 7
Abdil Hamid
@ForensicBlockSmith • Feb 13, 2026

Feb 13, 2026
1.7K

Hardhat vs Remix for beginners: when building a dApp, what should I use and why?

Hey everyone — I’m new to Ethereum development and building a small dApp (Solidity + ethers.js).I keep seeing “use Hardhat”, but I’m still unclear what Hardhat is used for in...

Like 11 Replies 6
AuditWardenRashid
@AuditWarden • Feb 7, 2026

Feb 7, 2026
1.6K

Blockchain Developer vs Data Scientist for Singapore (from Germany): Which path gets hired + EP pass reality in 2025?

I keep seeing people debate blockchain developer vs data scientist, so I’m putting my real situation here. I’m currently based in Germany, and I’m trying to target Singapore roles (either...

Like 11 Replies 6
AnitaSmartContractSensei
@SmartContractSensei • Apr 18, 2026

Apr 18, 2026
3.3K

Rust dev moving into Web3 — how do you answer ‘Tell me about yourself’ without sounding like a blockchain newbie?

I’m a Rust dev (backend + performance stuff) and I’m interviewing for Web3 roles now. This sounds silly, but “Tell me about yourself” is the one question where I freeze,...

Like 11 Replies 6
Difficulty - Medium

Total Plays - 1,589

Allowed Time - 10 sec

Best time - 0.900

Which opcode is deprecated but still callable?

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#D

Explanation:
CALLCODE is deprecated due to unsafe context handling. It remains callable for backward compatibility but should never be used in new designs.

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AshishS
@Web3SecurityPro • Jun 2, 2026

Jun 2, 2026
2.3K

What skills actually matter for blockchain UI/UX design jobs in NFT platforms, decentralized identity, wallet onboarding, and metaverse products?

I keep seeing blockchain UI/UX design jobs mentioned around NFT platforms, metaverse products, decentralized identity apps, crypto wallets, and Web3 communities, but I am not sure what hiring teams actually...

Like 11 Replies 8
Lakshminarayan TV
@VCFxRV0 • Apr 11, 2026

Apr 11, 2026
1.4K

Is Anyone Hiring Blockchain Project Managers Right Now? What Skills Do Employers Want in 2025?

Are there any Blockchain Project Manager jobs open right now? I have managed tech projects and worked with blockchain, smart contracts, and decentralized apps. I use Agile methods, handle stakeholders,...

Like 11 Replies 6
Difficulty - Medium

Total Plays - 21

Allowed Time - 10 sec

Best time - 1.062

Why avoid multiple SSTOREs in a function?

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Explanation:
SSTORE is one of the most expensive operations and repeating it unnecessarily multiplies costs. Caching values into memory and writing once dramatically optimizes gas. This is foundational in gas-sensitive protocols.

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Difficulty - Medium

Total Plays - 47

Allowed Time - 10 sec

Best time - 0.758

Which hash function does Bitcoin use?

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Explanation:
Bitcoin uses the SHA-256 cryptographic hash function to secure transactions and link blocks in the blockchain. This algorithm produces a fixed 256-bit output, ensuring immutability and resistance to tampering. By using SHA-256, Bitcoin maintains trust, decentralization, and data integrity across the network

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Difficulty - Medium

Total Plays - 39

Allowed Time - 10 sec

Best time - 0.959

What does zk-SNARK stand for?

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Explanation:
zk-SNARKs are zero-knowledge proofs that improve blockchain privacy and scaling by verifying transactions without revealing sensitive data.

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Difficulty - Medium

Total Plays - 32

Allowed Time - 10 sec

Best time - 1.388

What is the purpose of the #[account] macro in Anchor?

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Explanation:
The #[account] macro in Anchor is used to define and validate account structures for Solana smart contracts. It simplifies account management and ensures data integrity.

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Difficulty - Medium

Total Plays - 27

Allowed Time - 10 sec

Best time - 2.943

Which Rust feature ensures type safety in blockchain data structures?

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Explanation:
Rust’s ownership model enforces strict rules on data access, preventing issues like double-spending in blockchain applications. It ensures compile-time safety for complex data structures.

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Difficulty - Medium

Total Plays - 30

Allowed Time - 10 sec

Best time - 1.424

Which platform focuses on NFT-based games?

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Explanation:
Decentraland is a virtual world where users buy land and items as NFTs. It blends gaming and digital ownership.

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Difficulty - Medium

Total Plays - 30

Allowed Time - 10 sec

Best time - 1.157

MetaMask" is a

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Explanation:
MetaMask is a popular cryptocurrency wallet and browser extension that allows users to manage Ethereum-based assets and interact with decentralized applications (dApps). It securely stores private keys, enabling seamless transactions and access to Web3 platforms directly from the browser.

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Difficulty - Medium

Total Plays - 47

Allowed Time - 10 sec

Best time - 1.211

Blockchain Oracles provide

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Explanation:
A blockchain oracle is a service that connects a blockchain with real-world data from outside the network. It helps smart contracts get information like weather, prices, or sports scores so they can work properly.

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Difficulty - Medium

Total Plays - 40

Allowed Time - 10 sec

Best time - 0.706

What does Web3 rely on?

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Explanation:
Web3 uses blockchain to power trustless, decentralized applications.

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Amanda Smith
@AmandaS • Oct 24, 2024

Oct 24, 2024
1.5K

What’s a key reason to consider adopting a blockchain solution?

I’ve been thinking about how blockchain could help solve some of the inefficiencies in supply chain management. For instance, if you could have real-time, tamper-proof tracking of every shipment, wouldn’t...

Like 11 Replies 2
Shubhada Pande
@ShubhadaJP • May 30, 2026

May 30, 2026
2.0K

Salary, Tokens & Compensation Hub: Token Offers, Stablecoin Payroll, Salary Negotiation, and Global Pay Tradeoffs

Compensation is one of the highest-intent topics in Web3 job search. This hub is AOB’s classification layer for compensation-related questions across the platform. It groups together discussions and articles on...

Like 10 Replies 2