Solidity is a language for creating Blockchain smart contracts.

You can use it to create smart contracts, on more than 200…

It’s so exhausting to keep up with all these new DeFi projects. 

But very few DeFi projects are really original.…

Manipulating strings in Solidity is notoriously difficult. This is surprising for most developers who are used to manipulating easily in other programming languages like Javascript or Python. https://youtu.be/gNlwpr3vGYM In this article I give a couple of useful code snippets to do some simple string manipulations in Solidity. Warning: Keep in…

Generating a random number in a smart contract is very useful, especially for games. Can we do this in Solidity? Yes! https://youtu.be/4zvvZf-byok Here is the code: pragma solidity ^0.6.0; contract MyContract { function _randModulus(uint mod) internal returns(uint) { return uint(keccak256(abi.encodePacked( now, block.difficulty, msg.sender) )) % mod; nonce++; return rand; }…

ERC this, ERC that... so many token standards... If you want to become good in Solidity, you HAVE to understand how to transfer on-chain assets... And that means knowing token standards, like ERC20... The problem is... there are SO MANY token standards: What is an Ethereum Token? Which tokens are…

When you develop decentralized applications, you quickly stumbled upon this weird concept of "gas". That's very confusing for a lot of developers... But it's actually not that hard, if you ask the right questions. In this article, I will explain gas with 6 super easy questions and answers. https://youtu.be/ROBSk8DmWiE 1.…

Let's say we have 2 smart contracts. A and B. A calls B, and B throws an error. What happen in A? Not sure? haha, that's a tricky one! Actually it depends on how B was called. If B was called the normal way, the whole transaction get reverted: contract A {…

https://youtu.be/-5j6Ho0Bkfk ERC20 tokens allow you to create your own coin inside Ethereum.  They are used in many projects to represent financial assets, in-game assets, collectible, and other kind of assets. At some point in your project, you will probably need to interact with them. And most often, you will need to…

https://youtu.be/_Nvl-gz-tRs Sending Ether between smart contracts is very important. After all, it's because smart contracts can do financial transactions that they are so powerful. But surprisingly there are a few caveats when you want to send ether from a smart contract: Transfer units are in wei (10^-18 ether), not ether…

https://youtu.be/MPBOnChpi0c Solidity arrays... are like Javascript arrays, right? Nope.. In Solidity: Arrays can only contain data of the same type (ex: arrays of integers, array of booleans, but not arrays of integers AND booleans..) Arrays can be in storage, or in memory (persistent and non-persistent) You can use the `push()`…