Hard-level statistics interview questions covering advanced inference, multiple comparisons, non-parametric methods, and complex experimental design. Q1: Explain the multiple comparisons problem and how to address it. Answer: The Problem When testing multiple hypotheses simultaneously, probability of at least one Type …

Hard-level backend interview questions covering distributed systems, advanced architecture, and complex system design. Q1: Design a distributed caching system (like Redis Cluster). Answer: Consistent Hashing Implementation 1package main 2 3import ( 4 "fmt" 5 "hash/fnv" 6 "sort" 7 "sync" …

Hard-level Cardano interview questions covering advanced optimization and formal verification. Q1: How do you formally verify Plutus contracts? Answer: Formal Verification: Use Agda/Coq for proofs Prove contract properties Ensure correctness Mathematical guarantees Q2: How do you optimize for Cardano's execution model? …

Hard-level Cosmos chain operation questions covering advanced algorithms, performance optimization, and complex validator management. Q1: How do you implement advanced consensus optimizations and reduce latency? Answer: Optimistic Execution: 1type OptimisticExecutor struct { 2 pendingTxs map[string]*PendingTx 3 …

Hard-level Cosmos SDK interview questions covering advanced SDK internals, performance optimization, and complex module design. Q1: How do you implement a custom ABCI application with advanced state management? Answer: Custom BaseApp: 1package app 2 3import ( 4 "github.com/cosmos/cosmos-sdk/baseapp" 5 …

Hard-level frontend interview questions covering advanced patterns, performance optimization, and complex architectures. Q1: Explain React Fiber architecture and reconciliation. Answer: Fiber Architecture Reconciliation Phases Priority Levels Concurrent Features 1import { useTransition, useDeferredValue } from …

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 // …

Hard-level Protocol Buffers interview questions covering advanced topics, performance optimization, and complex scenarios. Q1: How does Protocol Buffer encoding work internally? Answer: Varint Encoding: Variable-length encoding for integers Smaller numbers use fewer bytes Most significant bit indicates continuation …

Hard-level Solana interview questions covering advanced optimization, security, and complex program design. Q1: How do you implement advanced account compression and state optimization? Answer: State Compression: 1// Use Merkle trees for state 2use merkle_tree::MerkleTree; 3 4pub struct CompressedState { 5 tree: …

Hard-level Web3 interview questions covering MEV, zero-knowledge proofs, advanced DeFi, and protocol design. Q1: Explain MEV (Maximal Extractable Value) and mitigation strategies. Answer: Sandwich Attack MEV Mitigation 1// ✅ Use private mempools (Flashbots) 2// ✅ Implement slippage protection 3contract MEVProtected { 4 …

Hard-level AI/ML interview questions covering advanced architectures, optimization, and theoretical concepts. Q1: Implement attention mechanism from scratch. Answer: How It Works: Attention allows model to focus on relevant parts of input when producing output. Core Idea: Compute weighted sum of values, where weights …

Hard-level software architecture interview questions covering advanced distributed systems, consensus, and complex patterns. Q1: Explain distributed consensus algorithms (Raft, Paxos). Answer: Problem: How do multiple nodes agree on a value in presence of failures? Raft Algorithm Roles: Leader: Handles all client …

Hard-level algorithm interview questions with detailed approach explanations and solutions. Problem 1: Median of Two Sorted Arrays Problem: Find median of two sorted arrays in $O(\log(m+n))$ time. Example: 1Input: nums1 = [1,3], nums2 = [2] 2Output: 2.0 3Explanation: merged = [1,2,3], median = 2 Approach Key Insight: …