Blog

Writing on agentic AI, blockchain, and AI systems architecture.

Technical writing by Mudassir Khan — agentic AI consultant and AI systems architect. New posts published directly on this site. Earlier writing on Dev.to.

Blockchain & Web3

Ethereum, Solana, smart contracts, wallets, on-chain transactions, and ERC token standards.

Cover illustration for: Solidity for Loop: Syntax, Patterns, and Gas Tips
BlockchainSoliditySmart Contracts13 min read

Solidity for Loop: Syntax, Patterns, and Gas Tips

Master the Solidity for loop. Counter syntax, break and continue, four iteration patterns, the unchecked-increment gas optimization

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Cover illustration for: while Loop in Solidity: Binary Search and Sentinel Patterns
BlockchainSoliditySmart Contracts13 min read

while Loop in Solidity: Binary Search and Sentinel Patterns

Master the Solidity while loop. Binary search with overflow-safe midpoint, unbounded loop dangers, four common mistakes, and a complete SortedBidList

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Cover illustration for: do-while Loop in Solidity: Slot Scanning and At-Least-Once Patterns
BlockchainSoliditySmart Contracts11 min read

do-while Loop in Solidity: Slot Scanning and At-Least-Once Patterns

Master the Solidity do-while loop. The at-least-once guarantee, slot scanning patterns, wrap-around search, four common mistakes, and a complete SlotReserver

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Cover illustration for: Loop Gas Optimization in Solidity: Five Techniques
BlockchainSoliditySmart Contracts12 min read

Loop Gas Optimization in Solidity: Five Techniques

Cut loop gas costs in Solidity with five proven techniques: cache array length, unchecked ++i, prefix increment, memory accumulators, and single SSTORE

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Cover illustration for: Loops with Mappings in Solidity: Enumerable Pattern
BlockchainSoliditySmart Contracts14 min read

Loops with Mappings in Solidity: Enumerable Pattern

Iterate over Solidity mappings safely. Enumerable mapping pattern, pull over push for unbounded sets, paginated reads

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Cover illustration for: Solidity Mapping with address: Patterns and Full Contract
BlockchainSoliditySmart Contracts13 min read

Solidity Mapping with address: Patterns and Full Contract

Learn how to use address as a key and value in Solidity mappings. Balance tracker, ownership registry, approval grant, and freeze flag with a complete smart

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Cover illustration for: Solidity Mapping with uint256: Voting and Leaderboard Patterns
BlockchainSoliditySmart Contracts13 min read

Solidity Mapping with uint256: Voting and Leaderboard Patterns

Learn how to use uint256 as key and value in Solidity mappings. Voting tallies, leaderboards, staking counters, and a complete governance contract

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Cover illustration for: Solidity Mapping with bool: Whitelist and Access Control
BlockchainSoliditySmart Contracts12 min read

Solidity Mapping with bool: Whitelist and Access Control

Learn how to use bool as a mapping value in Solidity. Whitelist gates, role access control, and presale guards with complete smart contract examples and gas

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Cover illustration for: Nested Mapping in Solidity: ERC20 Allowance and Two-Key Patterns
BlockchainSoliditySmart Contracts14 min read

Nested Mapping in Solidity: ERC20 Allowance and Two-Key Patterns

Learn nested mappings in Solidity. How ERC20 allowance works, the two-step keccak256 storage derivation, and a complete AllowanceToken contract with approve

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Cover illustration for: Solidity Mapping with bytes32: Document Registry and Role Identifiers
BlockchainSoliditySmart Contracts13 min read

Solidity Mapping with bytes32: Document Registry and Role Identifiers

Learn how to use bytes32 as a mapping key in Solidity. Document registries, keccak256 role identifiers, and hash-based storage patterns with complete smart

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Cover illustration for: uint Array in Solidity: A Beginner Smart Contract Guide
BlockchainSmart ContractsSolidity16 min read

uint Array in Solidity: A Beginner Smart Contract Guide

Learn the uint array in Solidity end to end. push, pop, delete, swap and pop, memory arrays, fixed length, and a Remix contract with every method.

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Cover illustration for: int Array in Solidity: A Beginner Smart Contract Guide
BlockchainSmart ContractsSolidity16 min read

int Array in Solidity: A Beginner Smart Contract Guide

Learn the int array in Solidity end to end. push, pop, delete, swap and pop, signed values, memory arrays, fixed length, and a Remix contract

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Cover illustration for: string Array in Solidity: A Beginner Guide With Code
BlockchainSmart ContractsSolidity16 min read

string Array in Solidity: A Beginner Guide With Code

Learn the string array in Solidity end to end. push, pop, delete, swap and pop, the memory keyword, fixed length, and a Remix contract with every method.

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Cover illustration for: address Array in Solidity: Beginner Guide With Code
BlockchainSmart ContractsSolidity16 min read

address Array in Solidity: Beginner Guide With Code

Learn the address array in Solidity end to end. push, pop, delete, swap and pop, the zero address, memory arrays, and a Remix Whitelist with every method.

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Cover illustration for: Struct Array in Solidity: A Beginner Smart Contract Guide
BlockchainSmart ContractsSolidity17 min read

Struct Array in Solidity: A Beginner Smart Contract Guide

Learn the struct array in Solidity end to end. push, pop, delete, swap and pop, field updates, memory and storage, and a Remix StudentRegistry contract.

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Cover illustration for: Create an ERC20 Token: Remix Step by Step
BlockchainAI Engineering13 min read

Create an ERC20 Token: Remix Step by Step

Build an ERC20 token from scratch and deploy it on Remix IDE. Full interface, contract code, deploy walkthrough, and the approve and transferFrom pattern.

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Cover illustration for: Create an ERC721 NFT in Remix: Step-by-Step Tutorial
BlockchainAI Engineering14 min read

Create an ERC721 NFT in Remix: Step-by-Step Tutorial

Build a complete ERC721 NFT contract on Remix IDE, end-to-end. Full IERC721 interface, mint and transfer code, IPFS metadata, safeTransferFrom receiver

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Cover illustration for: Create an ERC1155 Multi Token: Remix Tutorial
BlockchainAI Engineering14 min read

Create an ERC1155 Multi Token: Remix Tutorial

Build an ERC1155 multi token contract on Remix IDE. Full interface, batch operations, mint and transfer code, and a deployable game ready example.

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Cover illustration for: ERC-1155 With OpenZeppelin: A Beginner Tutorial With Code
BlockchainSolidity16 min read

ERC-1155 With OpenZeppelin: A Beginner Tutorial With Code

Learn ERC-1155 with OpenZeppelin from zero. Six Solidity examples: single mint, batch mint, safe transfers, metadata URIs, and a game inventory.

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Cover illustration for: Solana vs Ethereum: Blockchain Fundamentals Compared
BlockchainAI Architecture13 min read

Solana vs Ethereum: Blockchain Fundamentals Compared

Solana vs Ethereum — which blockchain should you build on? Distributed ledgers, Proof of History vs Gasper consensus, speed vs decentralization

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Cover illustration for: Blockchain Networks: RPC, Chain IDs, and MetaMask Setup
BlockchainAI Architecture13 min read

Blockchain Networks: RPC, Chain IDs, and MetaMask Setup

Public RPC endpoints are rate limited. How RPC nodes work, mainnet vs testnet, Chain IDs, and how to add a custom network to MetaMask with Alchemy.

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Cover illustration for: Solidity Smart Contracts: Complete Beginner Guide
BlockchainAI Engineering14 min read

Solidity Smart Contracts: Complete Beginner Guide

Solidity is the language for Ethereum smart contracts. This guide covers variables, functions, loops, control flow, and your first deployable contract.

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Cover illustration for: Solidity Mapping with Struct: Patterns and Examples
BlockchainSolidity14 min read

Solidity Mapping with Struct: Patterns and Examples

Mapping with struct is Solidity's workhorse for per-user state. Learn the pattern, see a full voting registry, master storage packing, and avoid

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Cover illustration for: Solidity Arrays with Loops: Smart Contract Examples
BlockchainSolidity13 min read

Solidity Arrays with Loops: Smart Contract Examples

Arrays plus loops in Solidity: for vs while, the vote tally pattern, the unbounded loop bug, pagination, and pull over push. Six patterns

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Cover illustration for: Solidity Arrays From Scratch: A Practical Guide
BlockchainSolidity12 min read

Solidity Arrays From Scratch: A Practical Guide

Learn arrays in Solidity from scratch. Fixed and dynamic arrays, push, pop, length, delete, storage vs memory vs calldata, plus a full worked contract.

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Cover illustration for: Build a Solidity Calculator Contract: Beginner Tutorial
BlockchainSolidity10 min read

Build a Solidity Calculator Contract: Beginner Tutorial

Build a Solidity calculator smart contract from scratch. Add, subtract, multiply, divide with pure functions, stored state, events, and require

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Cover illustration for: Solidity vs. Rust: Smart Contract Languages
BlockchainAI Engineering13 min read

Solidity vs. Rust: Smart Contract Languages

Solidity powers Ethereum DeFi. Rust powers Solana's Sealevel parallel runtime. Here is how the two languages differ on safety, performance, learning curve

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Cover illustration for: How Ethereum Wallets Work: Keys, Addresses, Signing
Blockchain9 min read

How Ethereum Wallets Work: Keys, Addresses, Signing

How an Ethereum wallet actually works — private and public keys, address derivation, seed phrases, and how a signed transaction proves ownership

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Cover illustration for: How Ethereum Transactions Work: Lifecycle and Gas
Blockchain10 min read

How Ethereum Transactions Work: Lifecycle and Gas

An Ethereum transaction is a signed message. This guide walks through every field, the wallet to mempool to block lifecycle, gas pricing

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Cover illustration for: ERC Token Standards Explained: ERC20, ERC721, ERC1155, ERC1400, ERC4337, ERC6551
Blockchain11 min read

ERC Token Standards Explained: ERC20, ERC721, ERC1155, ERC1400, ERC4337, ERC6551

All major ERC token standards explained — ERC20 fungible tokens, ERC721 NFTs, ERC1155 multi-token, ERC1400 security tokens, ERC4626 vaults

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Cover illustration for: Crypto Wallets: Setup to Your First Transaction
Blockchain13 min read

Crypto Wallets: Setup to Your First Transaction

What a crypto wallet actually stores, the difference between custodial and non-custodial, and a step by step guide to installing MetaMask and Phantom

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More posts coming soon

A 30-post technical series on agentic AI architecture, LangGraph patterns, blockchain compliance engineering, and production AI systems is in progress. Follow on Dev.to or LinkedIn to be notified.

FAQ

Frequently asked questions

When should I hire an agentic AI consultant?

Hire an agentic AI consultant when your team needs to build autonomous, multi-step AI workflows — such as agents that browse the web, call APIs, or orchestrate multi-model pipelines — and lacks in-house experience with LangGraph, tool-use reliability, or production agent safety. A consultant is faster than hiring a full-time engineer if your timeline is under 6 months.

What is the difference between RAG and fine-tuning?

RAG (Retrieval-Augmented Generation) fixes knowledge gaps by injecting relevant documents at inference time — ideal for private or frequently updated data. Fine-tuning fixes behaviour gaps by adjusting model weights on curated examples — best when you need consistent tone, output format, or domain-specific reasoning. In 2026, most production systems use both: a fine-tuned model as the base, with RAG for dynamic knowledge retrieval.

What does an AI systems architect do?

An AI systems architect designs the end-to-end infrastructure for AI products — including model selection, data pipelines, vector stores, agent orchestration, evaluation frameworks, and deployment strategy. Unlike an ML engineer who focuses on model training, or a data scientist focused on analysis, an AI systems architect owns the full production system design.

What is the difference between Ethereum and Solana?

Ethereum uses the Gasper consensus mechanism (Proof of Stake + Casper FFG), prioritising security and decentralisation over speed — it processes roughly 15–30 TPS. Solana uses Proof of History combined with Tower BFT, achieving 2,000–65,000 TPS at lower cost, but with greater centralisation risk. Ethereum is preferred for DeFi and high-value applications; Solana suits high-frequency, low-cost use cases.

What are multi-agent design patterns in production AI?

The four multi-agent patterns that work reliably in production are: Sequential (agents chain output to input in a fixed order), Orchestrator-Worker (a coordinator agent delegates tasks to specialised sub-agents), Hierarchical (nested orchestration across multiple management levels), and Dynamic Handoff (agents route tasks to the best-suited agent at runtime). LangGraph is the most common framework for implementing all four.

Should I hire an AI engineer full-time or use a consultant?

Use a consultant if you need a working system in 1–3 months, have a defined scope, or are pre-Series A. Hire full-time when you have a live product requiring ongoing iteration, a team to mentor, and 6+ months of runway budgeted for the role. The hybrid model — consultant to build the initial system, then a mid-level engineer to maintain it — is what most seed-stage teams in 2026 actually use.

Blog — Agentic AI, Blockchain & AI Architecture Writing