the go-to place to learn Solidity and Web3

Articles, step-by-step guides, and tips about Solidity, Web 3 and Smart Contracts

Latest guides

solidity fundamentals

New to Solidity? start here! You will find all the basics to understand how to start writing smart contracts.

metamask

Are you building a web 3 app? Metamask is the most used wallet so understanding how to interact with it is a must.

step-by-step guides

Detailed tutorials about how to create web3 apps. From the smart contracts to the front-end and deployments.

September 16, 2022

The keccak256 hashing method explained

In this article we explain what is the keccak256 hashing method and show some examples..

June 11, 2022

Automatically adding a blockchain to Metamask with Javascript

A detailed guide about how to create a button that automatically adds a blockchain to Metamask. No need to enter blockchain details manually

May 21, 2022

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.

May 16, 2022

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.

May 11, 2022

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

May 9, 2022

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.

April 21, 2022

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.

April 11, 2022

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.

March 31, 2022

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.

March 6, 2022

How to transform JavaScript number to token amount

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

February 10, 2022

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.

February 1, 2022

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.

January 27, 2022

Ethernaut hacking challenges: intro walkthrough

An introduction to Ethernaut, a smart contract hacking game to learn solidity advanced concepts, common hacks, and vulnerabilities.

January 24, 2022

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

January 11, 2022

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

January 6, 2022

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.

January 4, 2022

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

January 2, 2022

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.

December 27, 2021

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.

December 22, 2021

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

December 20, 2021

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.

December 1, 2021

How to emit and capture smart contract events

Introduction to solidity events and how to define, trigger, and capture them in a web3 application

November 21, 2021

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.

November 17, 2021

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.

November 15, 2021

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

November 13, 2021

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.

November 11, 2021

Solidity fundamentals: data location (storage vs memory)

A quick review of the different places where you can store variables in Solidity: storage and memory

November 8, 2021

Math operations in Solidity: the basics

A quick guide describing how to do basic mathematical operations in Solidity

November 3, 2021

Solidity fundamentals: all about functions

A detailed guide about functions in Solidity explaining how to declare them, return statements, visibility, and types (view and pure)

November 1, 2021

Solidity fundamentals: complex data types

Continuation of the previous article about data types, now reviewing complex way to store and handle data using structs, arrays and mappings.

Featured on Tech-Blogs.dev

Browse solidity articles by category