the go-to place to learn Solidity and Web3
Articles, step-by-step guides, and tips about Solidity, Web 3 and Smart Contracts
New to Solidity? start here! You will find all the basics to understand how to start writing smart contracts.
Are you building a web 3 app? Metamask is the most used wallet so understanding how to interact with it is a must.
Libraries in Solidity: how to create, use them, and most popular
In this article we'll learn what are libraries in solidity, the difference between using a library or contract inheritance, and review the most popular ones.
Error handling with throw and revert: differences and gas usage
In this article cover error handling in Solidity using throw, revert and require see the differences in how they consume gas.
How to create, sign, and send transactions manually with Ethers
Explaining how to send blockchain transactions programatically using Ethers. This example is useful to send transactions from a backend or when you don't have a wallet and need to sign the transactions manually
The keccak256 hashing method explained
In this article we explain what is the keccak256 hashing method and show some examples..
A detailed guide about how to create a button that automatically adds a blockchain to Metamask. No need to enter blockchain details manually
Easy way to monitor pending transactions from the mempool
Here is a quick way to monitor pending transactions from a blockchain transaction pool connecting via websocket to a node.
Interact with other contracts using contract Interfaces
In this article we review what are smart contract interfaces in solidity and how to use them to interact with other contracts in the blockchain.
How to get a smart contract balance
A detailed explanation of how to obtain the balance of a contract from the contract itself and for other contracts
Introducion to GoEthereum (Geth): installation and first steps
Explanation of different clients used in blockchain nodes and how to install GoEthereum locally to interact with a node.
Simple way to concatenate strings in Solidity
In this quick tip I explain how to concatenate strings in Solidity and why it's done this way.
Generating random numbers in Solidity easily
Here is a quick way to generate semi random numbers in Solidity without using external contracts or an oracle.
How to send blockchain transactions from a backend
Explaining how to send blockchain transactions from a backend and understanding what Metamask does for us behind the scenes.
Quick guide explaining how to use utility methods to transform a user input into a valid amount to transfer ETH or other ERC20 tokens in your web3 app
Ethernaut hacking challenges: level 2 Fallout walkthrough
A walktrough of Ethernaut's smart contract hacking game second level, in which you can learn about constructors.
Ethernaut hacking challenges: level 1 walkthrough
A walktrough of Ethernaut's smart contract hacking game first level, in which you can learn about fallback functions.
Ethernaut hacking challenges: intro walkthrough
An introduction to Ethernaut, a smart contract hacking game to learn solidity advanced concepts, common hacks, and vulnerabilities.
How to send ETH from a web3 app to a smart contract
A quick article explaining a very common scenario in web3 apps: sending ETH from a user's account to a smart contract
How to detect and switch Metamask chain in a web3 app
A detailed guide about how can you detect the network that Metamask is connected to and switch to the one your web3 app uses
Step-by-step Web3 DApp built with Solidity and Vue.js (part 3)
Third part of this guide in which I explain how to create a simple message board web3 app. In this part I explain how to deploy both the front end and the smart contract.
How to deploy your smart contract to Rinkeby
A step-by-step guide explaning how to deploy a smart contract to the Rinkeby Ethereum test net using Alchemy
Step-by-step Web3 DApp built with Solidity and Vue.js (part 2)
Second part of this guide in which I explain how to create a simple message board web3 app. In this part we focus on the front end and the smart contract integration.
Step-by-step web3 DApp built with Solidity and Vue.js (part 1)
Step-by-step guide to create a basic smart contract project with Hardhat that reads and writes messages in a blockchain.
Solidity fundamentals: working with dates and time
Another quick article with everything you need to know about how to handle dates and time in solidity smart contracts
Web3.0 template project using Vue.js, Typescript, and TailwindCSS
I've created a basic template that I can use in multiple web 3.0 projects. It includes Metamask integration out of the box.
How to emit and capture events in Solidity
Introduction to solidity events and how to define, emit, and capture them in a web3 application
Simple way to compare strings in Solidity
Comparing strings is something very common in programming languages but in Solidity we do it a little different.
Solidity fundamentals: require conditional
The require conditional is very common in Solidity as it stops the exeution of a function if a condition is not true.
Solidity funcions visibility: public, private, internal and external
A detailed guide about functions visibility in Solidity explaining the difference between public and private, and internal and external
Solidity fundamentals: Global variables (msg, this & block)
Solidity offers a range of global variables that we can access in our smart contracts.These global variables provide information about the blockchain.
Featured on Tech-Blogs.dev