Polkadot consensus algorithm interview questions covering Nominated Proof-of-Stake (NPoS) with BABE and GRANDPA. Q1: How does Polkadot (NPoS) consensus work? Answer: Polkadot uses Nominated Proof-of-Stake (NPoS) with BABE + GRANDPA. Sequence Diagram: sequenceDiagram participant Leader participant Validator1 participant …

Easy-level Polkadot interview questions covering blockchain basics, Substrate, and parachains. Q1: What is Polkadot and how does it work? Answer: Polkadot is a heterogeneous multi-chain protocol. graph TB A[Polkadot] --> B[Relay Chain] A --> C[Parachains] A --> D[Parathreads] B --> E[Validators] B --> F[Collators] B …

Hard-level Polkadot interview questions covering advanced optimization and complex parachain design. Q1: How do you implement advanced runtime upgrades? Answer: Runtime Upgrades: 1pub struct CustomUpgrade; 2 3impl OnRuntimeUpgrade for CustomUpgrade { 4 fn on_runtime_upgrade() -> Weight { 5 // Migration logic 6 // …

Medium-level Polkadot interview questions covering advanced Substrate development and parachain architecture. Q1: How do you implement custom consensus in Substrate? Answer: Custom Consensus: 1use sc_consensus::{BlockImport, BlockImportParams}; 2 3pub struct CustomBlockImport; 4 5impl BlockImport<Block> for …

Core principles, consensus mechanisms, and key innovations of major blockchain platforms. Bitcoin (BTC) Core Principles Digital gold: Store of value, not programmable Decentralization: ~15,000 full nodes worldwide Security: Most secure blockchain (highest hash rate) Simplicity: Intentionally limited functionality …