# Week 3 at BlockFuse Labs: Building the Web3 Mindset Web3 is more than just writing smart contracts or deploying dApps. It is about reimagining how the internet works. It is a shift from centralized control to user ownership, from black-box systems to transparent protocols. In Week 3 of the BlockFuse Labs Cohort III Web3 Bootcamp, under the expert guidance of Shuaibu Suleman, we continued laying the theoretical groundwork for that future. Though we have not started building yet, what we are constructing now is even more powerful the mindset and understanding required to become real Web3 builders. This week was all about demystifying the Ethereum blockchain and understanding its inner workings. Every concept we discussed is essential for anyone who wants to build or even just meaningfully engage with Web3. Here is a breakdown of the key topics we covered. ### Transactions A transaction is simply an action initiated by a user or smart contract. Whether you are sending ETH, calling a function in a smart contract, or deploying a new contract, you are making a transaction. Each transaction contains: - A nonce to ensure uniqueness - A gas limit that defines how much computation you are paying for - A gas fee that sets how much you are paying per unit of gas - The recipient address, value, and optional data Transactions form the building blocks of all activity on-chain. ### Transaction Types Ethereum supports multiple transaction types: 1. Legacy Transactions 2. Access List Transactions (EIP-2930) 3. Dynamic Fee Transactions (EIP-1559) The newer transaction types, especially those introduced after EIP-1559, were designed to make gas fees more predictable and efficient. ### Opcodes Opcodes are the low-level instructions that the Ethereum Virtual Machine (EVM) executes. Think of them as the assembly language of Ethereum. Examples include: - ADD for adding two numbers - SSTORE for storing a value in contract storage - CALL for calling another contract Understanding opcodes helps us see how smart contracts truly operate under the hood. ### Ethereum Upgrades and EIPs Ethereum evolves through community proposals called Ethereum Improvement Proposals, or EIPs. These proposals suggest changes and upgrades to the Ethereum network. Notable EIPs we explored include: **EIP 1559** — Introduced a base fee and priority fee model to replace manual gas pricing. It burns the base fee, making ETH deflationary over time. **EIP 3675** — Marked the transition from Proof of Work to Proof of Stake, reducing Ethereum’s energy consumption by over 99 percent. **EIP 2930** — Introduced access lists to reduce gas costs by allowing transactions to specify which addresses and storage slots they will access. **EIP 4844** — Also known as Proto-Danksharding, it adds temporary data blobs to prepare Ethereum for full sharding, helping Layer 2 rollups scale efficiently. **EIP 4337** — Enables account abstraction, allowing for smart contract-based wallets with features like social recovery and gasless transactions. ### Blocks A block is a collection of transactions bundled together. Every block contains: - A list of validated transactions - The hash of the previous block - Metadata such as timestamps and gas usage Blocks form the chain in blockchain, ensuring continuity and security. ### Nodes A node is any computer running Ethereum software. Nodes perform critical roles in the network: - They validate transactions and blocks - They relay information across the network - They store a copy of the entire blockchain Nodes form the backbone of the decentralized Ethereum ecosystem. ### Clients: Execution and Consensus After Ethereum’s transition to Proof of Stake, it now uses two types of clients: - Execution Clients, such as Geth and Nethermind, which handle transaction execution and maintain the state - Consensus Clients, such as Lighthouse and Prysm, which coordinate validator actions and maintain consensus This separation improves performance, decentralization, and security. ### Validators Validators replaced miners in Ethereum’s Proof of Stake system. Their responsibilities include: - Staking 32 ETH to participate - Proposing and attesting to new blocks - Earning rewards or being penalized for dishonest behavior Validators are essential to the health and security of the Ethereum network. ### Gas Gas is the unit used to measure how much computational work is required to process a transaction or run a smart contract. Every action on Ethereum, such as transferring ETH or calling a function, requires gas. **Why Pay Gas Fees?** Gas fees serve three primary purposes: - They reward validators for securing the network - They prevent spam and misuse - They help prioritize transactions in times of high network demand **How Are Gas Fees Calculated?** Since the EIP-1559 upgrade, Ethereum uses a more dynamic fee structure that includes: - Base Fee: Set by the network and burned - Priority Fee: Optional tip to validators - Max Fee: The maximum amount a user is willing to pay **Formula:** `Gas Used × (Base Fee + Priority Fee) = Total Fee` This system improves gas predictability and supports Ethereum’s economic sustainability by reducing the supply through base fee burning. Gas is not just a technical detail. It is central to how Ethereum operates and evolves. Week 3 of the BlockFuse Labs Web3 Bootcamp was a pivotal chapter in our journey. Under the expert direction of Shuaibu Suleman, we explored vital concepts that every Web3 developer must master — transactions, gas, opcodes, validators, clients, blocks, and Ethereum’s constant innovation through community-driven proposals. Although we have not yet started writing code, we are building something just as important. We are learning how Ethereum works at a deep level, how to think like blockchain developers, and how to approach problems from a decentralized perspective. With this theoretical foundation in place, we are better prepared for the practical phase ahead. We are not just learning how to build on Web3. We are preparing to help shape its future.