The Official Polygon Tutorial Code Along - All Levels - DeFi

Explore how decentralized finance uses blockchain to remove intermediaries from traditional finance, and how smart contracts, lending, insurance, NFTs, DEXs, and oracles enable transparent, permissionless financial services.

Explore how decentralized finance enables direct lending and borrowing of digital assets via smart contracts, with collateralized loans via MakerDAO, lenders earning interest, and borrowers repaying principal and interest.

Explain centralized exchanges and decentralized exchanges, highlighting asset custody and intermediaries on CEXs versus smart contracts, liquidity pools, and wallet-based trading on DEXs.

Learn how stablecoins keep value by pegging to real-world assets such as the us dollar, using collateralized reserves, fiat, gold, or crypto backing, including examples like Tether and Dai.

Explore the rise and fall of TerraUSD and Luna, algorithmic stablecoins pegged to the dollar. Identify factors behind the 2022 collapse, including market downturn and liquidity gaps.

Learn how cryptocurrencies are tokens on blockchain networks that power gas fees, enable governance, and drive decentralized finance, exemplified by Bitcoin and ether.

Analyze whether cryptocurrencies are securities, noting that Bitcoin is treated as a commodity by the SEC, while many tokens lack a central issuer and profit promise. Clarity shapes crypto innovation.

Explore the ERC-20 standard on Ethereum, learn how fungible tokens are created as smart contracts, and see how Polygon uses bridges to connect to Ethereum in decentralized finance.

Explore how fungible tokens differ from non-fungible tokens, and learn how ERC721 enables ownership and trading of unique digital assets within decentralized finance.

Explore real NFT case studies, from Cryptopunk 7804's $7.6 million rise to cautionary rug pulls on dubious platforms, and learn how these digital assets intersect with decentralized finance.

Explore the difference between proof of work and proof of stake, and how validators stake cryptocurrency to add blocks and earn rewards on Polygon and Ethereum networks.

Explore Polygon's proof-of-stake sidechain architecture, focusing on bore as the block producer, Heimdall, and smart contracts within the EVM, which runs Solidity bytecode.

Heimdall, a layer-2 Polygon checkpointing component, consolidates blocks generated by Borr into checkpoints, creates lightweight hashes, and publishes them to the Ethereum network for faster transmission.

Explore how polygon's architecture deploys a set of smart contracts on the Ethereum mainnet, including the Matic token swap onto polygon and the checkpoints mechanism.

Explore polygon's architecture, balancing speed and cost through selective validation and checkpointing with bor and heimdall; learn stake-weighted random committee selection and ethereum-backed security.

Explore how smart contracts deploy on the blockchain, transfer ERC20 tokens, and use approval mechanisms, then set up the Replit IDE to deploy and test hands-on.

Learn to set up metamask and a first wallet, understand how Ethereum accounts, tokens, and networks work, and deploy smart contracts on the Polygon Mumbai test network using test tokens.

Learn to connect Metamask to the Polygon Mumbai testnet using Infura. Add the network manually and prepare your wallet and IDE for smart contract labs.

Connect MetaMask to Matic and fork the Polygon starter code to learn Solidity. Explore ERC-20 contracts and Openzeppelin patterns, deploy smart contracts with Replit, and study transfer from test workflow.

Learn to transfer MATIC test tokens on the Polygon Mumbai network, connect MetaMask, and use the faucet to obtain test funds for testing gas-based smart contracts.

deploy your first smart contracts on the matic mumbai testnet, including an erc20 token, a savings contract, and a manager, and learn token transfers, approvals, minting, and burning in solidity.

Deploy your first ERC-20 contract on Polygon, obtain its address, and connect it to a savings account and manager contract, while reviewing transaction hashes and explorer data.

Deploy three smart contracts in a DeFi workflow: an erc20 token, a savings contract, and a manager contract, using OpenZeppelin standards and MetaMask.

Learn how to add your custom ERC20 token to Metamask by importing its contract address, selecting the symbol and 18 decimals, and minting tokens in the next video.

Explore how ERC-20 token minting works, including public variables, access control, and the implications of minting by anyone versus restricted design, with Polygon vs Ethereum contrasts.

Learn how to mint tokens with 18 decimals in solidity using integers, understand tokenomics basics, and see how transfer from enables DeFi exchanges and lending.

Explain how the transfer from mechanism in the erc20 standard uses allowance and approve to let a spender move tokens, with nested mappings and defi use cases like dexes.

Demonstrates the end-to-end defi workflow by deploying and interacting with three smart contracts (erc-20 token, savings account, and wallet), covering token approval and transfers into the savings account.

Explore zero knowledge proofs (zkp) as an interactive proof system where a prover demonstrates secret knowledge to a verifier without revealing the secret, with privacy-preserving and blockchain authentication applications.

Zero knowledge proofs let a prover validate statements to a verifier without revealing data. Polygon uses zk rollups to aggregate off-chain transactions into a proof verified by Ethereum, fast finality.

The Polygon Xcp specification defines the format and the challenges the verifier must check against the prover's responses, enabling Ethereum to validate Xcp rollups and push them to the EVM.

Discover how zk proofs power Polygon ZK EVM as a scalable, secure EVM‑equivalent platform, then build and bridge dapps from the SSC EVM to Ethereum with a custom front end.

Learn the fundamentals of solidity and programming, including variables, data types, control structures, classes, contracts, mapping, and arrays, as you build a local NFT marketplace from scratch.

Code along in Remix Ethereum IDE to write, deploy, and test a fungible crypto token contract close to the ERC-20 standard on a test network, then transfer tokens.

Launch the crash course section by building a crypto token contract in Solidity for first-time coders, while outlining paths from zero to expert Solidity course.

Explore Solidity as the primary language for implementing smart contracts, the pragma Solidity line. Learn how Solidity powers NFT marketplace development on Ethereum and interfaces with JavaScript.

Select a compiler version with pragma solidity, using a precise version or a 0.8.x range, to ensure compatible solidity code and reliable IDE deployment.

Dive into writing a solidity smart contract by creating a named contract, using curly braces, and explicitly declaring data, while exploring object oriented concepts and inheritance.

Learn how to define a Solidity contract, declare the contract shell, and store token counts using an unsigned integer with explicit data types and visibility.

Deploy your first crypto token contract and compile to view live deployment data. Assign 400 tokens, observe gas costs, and verify deployment via the tokens button and console.

Explore Solidity visibility keywords (public, private, external, and internal) and see how the address type and msg.sender regulate who can mint tokens.

Practice Solidity visibility by creating a private totalSupply set to seven and a public sender address in a token contract, illustrating private versus public data in crypto tokens.

Learn to declare and access variables in Solidity by creating a private uint totalSupply and a public address sender, then test deployment and explore two comment styles.

Learn how constructors in Solidity are special functions that run immediately upon deployment, initialize values like the mentor address from the current caller, and can only run once.

Explore how mapping in solidity acts like a dictionary to store data by linking a key to a value, enabling address indexing.

Write a Solidity mapping that uses the address as the key and the integer balances as the value, and declare it as a public map.

Discover solidity events provide logging of changes and let clients react to sending and transferring tokens. Declare events using the event keyword and emit them with from, to, and amount.

Learn to design a mint function in Solidity that mints tokens to a receiver with a specified amount, using a balances mapping and owner-only access via require.

Learn to enforce access control in solidity with require, by comparing message sender to the minter, ensuring only the authorized account can mint tokens and reverts when unauthorized.

Organize Solidity contracts by grouping state variables, mappings, and constructor for clarity, then implement a mint function that updates balances[receiver] using the plus equals operator to add tokens.

Write a public send function in solidity that updates the sender's balance by decrementing the amount and increments the receiver's balance, then emit the send event.

Implement a public send function that updates the sender and receiver balances using minus equals and plus equals, then emits a send event with from, to, and amount.

Deploy and test your first mintable token contract by minting tokens, sending them between accounts, and verifying transactions on a test network, while learning the essential Solidity basics.

Take this optional section to strengthen Solidity basics, including variables, data types, arrays, and conditional logic, through hands-on Remix code-alongs on remix.ethereum.org, create topic files, and save progress locally.

Explore variables and types as memory locations that store and update values, with examples in pseudo code and a focus on efficient memory use in smart contracts.

Identify the three main variable types: booleans, integers, and strings, and note that in Solidity, bytes are often preferred over strings to save costs, since strings handle error messages.

Learn to declare and initialize Solidity variables in a learn variables contract, using uints, bools, and strings with camelCase and proper semicolon syntax.

Practice basic Solidity variables and types by declaring wallet as an integer, spend as a boolean, and notify spent as a string; initialize wallet to 500 and set spend accordingly.

Declare and initialize Solidity variables in a contract, including int wallet to 500, bool spend to false, and string notifySpend, to track wallets and spending.

Explore decision making in Solidity by using conditional statements, including if and if-else, to grant access based on password accuracy and user input.

Master if statements in Solidity through an oranges example, using equality checks and if-else logic to return booleans from a public function.

Learn basic decision making in Solidity by building an airdrop function tied to a staking wallet, using if-else to reward ten tokens or one and return the result.

Explore arrays in Solidity by declaring int arrays (including a fixed-size 200) and using push, pop, and length to add, remove, and count elements, with practical examples.

Learn how arrays work in Solidity by creating three arrays (including a fixed-size array), and master push, pop, and length to add, remove, and inspect elements.

Practice maintaining a compact Solidity array by implementing remove element that shifts the target to the last index, pops it, and verifies the length changes from 4 to 3.

Learn to compact an array by moving the last element into the target index, popping the end, and verifying with tests that push values and get length.

Explore abstract contracts in Solidity, where a function with no implementation makes a contract abstract, and learn how derived contracts override and inherit behavior.

Explore the terminal as a text-based command shell that lets you type and execute commands. Learn to navigate directories with cd and access the OS for development and programming tasks.

Discover how to navigate and customize the terminal, use dot and double-dot for directories, and apply asterisk wildcards and mkdir to build an efficient cross-platform command line environment for developers.

Set up a local nft marketplace by installing node.js, running JavaScript in the terminal, and learning how node.js enables scalable network apps.

Learn how to enter Node.js in the terminal, write JavaScript, and manipulate an array with push. Practice creating an empty array and adding three colors in Node.

Learn the basics of npm, the world's largest software registry, and how to install node and the npm command line interface, verify npm version, and install libraries for your projects.

Install Visual Studio Code, the cross-platform text editor, to edit code with debugging, syntax highlighting, snippets, and git integration; download from code.visualstudio.com.

Connect Metamask to the Polygon zkEVM test net, switch from Mumbai, and configure RPC URL, chain ID, and explorer for testing smart contracts with a front end.

Add test tokens to the ZK polygon network via faucet, connect with metamask, and verify the transfer on the explorer before the next lesson on ERC 721 and SSC EVM.

Explore out-of-the-box smart contracts with the OpenZeppelin Wizard, build ERC-721 NFT contracts with mintable and burnable options and safe minting, and learn deployment on the Ethereum virtual machine.

Clone the official polygon template from GitHub, install dependencies with npm, and run a local dev server using hardhat to build a web3 front end that interacts with MetaMask.

Review the zk evm stack front end code in Visual Studio Code, covering React components, JSX, state hooks, Material UI, CSS, and how to read project files and setup.

Install ethers and hardhat with npm, configure a .env for the private key, and copy your metamask private key to the project to deploy and test smart contracts.

Configure hardhat for a zkEVM project by setting solidity version, artifacts path, and networks, and wire in a private key (from env) and RPC URL to deploy counter contract.

Create a solidity counter smart contract from scratch using hardhat, including on-chain increment and view retrieval, while organizing contracts and considering gas efficiency and deployment steps.

Learn to deploy the counter contract on the blockchain with a hardhat script using ethers, log the deployed address, and handle constructor arguments and unlock times.

Deploy smart contracts on Polygon's zk evm testnet using devops and hardhat toolbox, compiling and deploying, then connect your front end for a layer two to layer one workflow.

Build a React front end that connects to a deployed counter contract via ethers. Import counter.json and the contract address, and fetch the on-chain count using an asynchronous useEffect.

Fetch on-chain counter data into a front-end app using ethers library and metamask integration. Use useEffect for asynchronous data retrieval and contract interactions, with error handling to display blockchain values.

Connects a React frontend to the Ethereum blockchain using ethers, requesting accounts, signing transactions, and incrementing a contract counter with a loading indicator.

Move the application from local state to on-chain counters and enable real-time updates. Learn to handle loading states, error resets, and effect changes to reflect blockchain activity.