Solidity *

In the world of blockchain, where the word "gas" is most often associated not with gas stations, but with fees for transactions in Ethereum, the search for ways to minimize these costs is becoming increasingly relevant. Less heartache for an empty wallet and more time to solve really important issues... for example, what to cook for lunch =)

Similar to the epic Batman vs Superman battle, compare GSN and Account Abstraction. As in any superhero story, each of them has its own unique abilities and disadvantages, which we will look at in detail.

Imagine: you've just created an incredible decentralized application, and it's so cool that even your grandmother wanted to try it. But once users are faced with the need to pay a commission, the entire UX (User Experience) rapidly slides down like a ball down a slide. Blockchain promises a bright future in which decentralization, transparency and security are our best friends, and it makes us pay for daily operations. Imagine if you had to pay every time you like on social networks or send a message in a messenger. It's terrible, isn't it? But dApps users face something like this every day.

But now, like a prince on a white horse, GSN (Gas Station Network) appears. With its help, developers can make their applications gas-less, and users will finally be able to forget about commissions like a nightmare.

In this article, we will look at what GSN is, how it works, and how to implement it into your projects to please users.

Hey! My name's Kirill Ziborov and I'm a member of the Distributed System Security team at Positive Technologies. In this article, I'll be continuing the discussion of methods and tools for the formal verification of smart contracts and their practical application to prevent vulnerabilities. The main focus will be on the deductive verification method, or more precisely, the ConCert framework for testing and verifying smart contracts.

Let’s imagine you need access to the real-time data of some smart contracts on Ethereum (or Polygon, BSC, etc.) like Uniswap or even PEPE coin to analyze its data using the standard data scientist/analyst tools: Python, Pandas, Matplotlib, etc. In this tutorial, I’ll show you more sophisticated data access tools that are more like a surgical scalpel (The Graph subgraphs) than a well-known Swiss knife (RPC node access) or hammer (ready-to-use APIs). I hope my metaphors don’t scare you ?.