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Arbitrage Bot DeFi DEX javascript solidity

Trading and Arbitrage on Ethereum DEX: Get the rates (part 1)

In this series of tutorials, we explore how to build solutions around trading and making simple arbitrage bot using Ethereum decentralized exchanges (DEX). This series uses Javascript, Solidity, and the 1inch dex aggregator and flash loans. As the subject is wide, we have split the series into several parts below: Get the exchange rates to […]

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Getting started javascript web3js

Listening to new transactions happening on the blockchain

A common use case of JavaScript programming with Ethereum is to listen to new blocks mined on the blockchain and looking at the content of the blocks for getting specific informations. This task is often used for example if you’d like to store all the blockhain data in a database or if you’d like to […]

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Getting started javascript web3js

Setup web3js to use the Ethereum blockchain in Javascript

In this tutorial, we’ll see how to get started with Web3JS to interact with the Ethereum blockchain. Web3js can be used both in frontends and backends to read data from the blockchain or make transactions and even deploy smart contracts. The first step is to include web3js in your project. To use it in a […]

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blog data analytics

Explore Ethereum Data with SQL queries on Dune Analytics

This tutorial will teach you how to query onchain data using the amazing Dune Analytics platform. Dune Analytics is the all-in-one destination to query, visualise, share and explore human readable smart contract data. It’s trusted by a lot of awesome companies like Gnosis, Compound and Bancor. For using the platform to make your own queries […]

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blog DeFi Getting started Tests

Testing your smart contract with existing protocols: Ganache fork

When you’re developping Ethereum contracts that interact with other Dapps and protocols like DeFi it’s important to be able to test your smart contracts agains the blockchain as you can’t re-deploy every smart contracts that your smart contract depends on. For this we’ll use Ganache from Truffle. Ganache is a program that lets you quickly […]

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erc20 solidity

Transfers and approval or ERC20 tokens from a solidity smart contract

In the previous tutorial we studied the anatomy of an ERC20 token in Solidity on the Ethereum blockchain. In this article we’ll see how we can use a smart contract to interact with a token using the Solidity language. For this smart contract, we’ll create a really dummy decentralized exchange where a user can trade […]

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blog

Every block explorers Ethereum developers should know about

In this article we’ll cover the most useful block explorers for developers and what we love about them. A block explorer is a user interface that let you explore blocks, transactions, accounts of the blockchain. Some offers useful API and other interesting aggregated data like sourcecode, events… Etherscan Etherscan is definitely the most popular block […]

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blog

Hack Money, a virtual hackathon to build DeFi applications.

A lot of hackers are stuck at home during the COVID-19 epidemy and ETHGlobal will make sure we will not get bored! After organizing 14 in-person hackathons around the world to accelerate the Ethereum ecosystem it’s now time for a hackathon anyone can participate from anywhere! The Hack Money hackathon will be accessible to anyone […]

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Getting started solidity

Interact with other contracts from Solidity

In the previous tutorials we learnt a lot how to deploy your first smart contract and add some features to it like control access with modifiers or error handling in Solidity. In this tutorial we’ll learn how to deploy a smart contract from an existing contract and interact with it. We’ll make a contract that […]

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Getting started solidity

Handle Errors in Solidity With Require and Revert

A good programmer is someone that can imagine and handle all the cases that will happens during the execution of the program. For this, Solidity offers different functions that we’ll cover in this article: require and revert. Require The require Solidity function guarantees validity of the condition(s) passed as parameter that cannot be detected before […]