Captain Link (@captainlink) • Hey

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**Here's the Paypal "X" thread key points** 1. PayPal USD ( $PYUSD ) is a U.S. dollar-denominated stablecoin that is designed to contribute to the opportunity stablecoins offer for payments. 2. It is 100% backed by US dollar deposits, short-term US treasuries and similar cash equivalents 3. $PYUSD is issued by @Paxos Trust, a trusted partner in the stablecoin space. 4. Eligible US paypal customers can purchase paypal USD and have the following capabilities: . *Transfer $PYUSD between PayPal and compatible* *external wallets* *. Convert any of PayPal supported crypto to and* *from $PYUSD* 5. Paypal USD is redeemable 1:1 for US dollars, providing a stable instrument that is both digitally native and easily connected to fiat currency like the US dollar. 6. This stablecoin launch may reduce friction for in-built payments in virtual environments, facilitate fast transfers of value and foster the expansion into digital assets by large brands. 7. PayPal USD is an ERC-20 token issued on the #Ethereum. This means it can be easily adopted by exchanges and integrated into external wallets and web3 apps. PayPal wrote in a press release. “***Most of the current volume of stablecoins is used in web3-specific environments — PayPal USD will be compatible with that ecosystem from day one and will soon be available on Venmo.***”
Reentrancy attacks A reentrancy attack is a type of vulnerability in a smart contract where a malicious contract exploits a function's external calls to re-enter and manipulate the original contract's state before the first invocation of the function is completed. This attack is primarily associated with smart contracts and can lead to the theft of funds or other unintended consequences.
SADBOY & BASTL - Marilyn Monroe STREAM : https://fhc.fanlink.to/marilynmonroe
Chainlink gives Use decentralization, trusted nodes, premium data, and cryptographic proofs to connect highly accurate and available data/APIs to any smart contract
Hey there, Web3 fellows, I am an independent security researcher transitioning from web2.0 to web3. I am really excited to be here and make web3 a safer place. I am looking forward to expand my network #lens #defi #smartcontracts 🙂
Last week, we shared how @lensprotocol built Momoka, its innovative scaling solution, using Bundlr Let's dive into what that means 👇🏾 Momoka uses Bundlr for scalable storage and ordering, and Polygon for smart contract interactions One of the most significant challenges of this hybrid approach was maintaining transaction order across the two different systems Lens solved this problem with a simulation solution that guarantees the real-time chronological sequence of user transactions, regardless of whether they are posted to Polygon or Bundlr 🚀 Bundlr as a storage and ordering layer is 1000x more cost-effective with 700x lower latency. Since launching last week the average Momoka transaction cost is only $0.0005 🤯 Bundlr's ordering service is fully permissionless, and is detailed in our docs 🤝 https://docs.bundlr.network/overview/services/ordering Stay tuned for one more exciting announcement from Bundlr and Lens. In the meantime, dive into our blog post on how Momoka was built using Bundlr 🌟 https://bundlr.mirror.xyz/oDs2P54Esh9Tmi8OIL7KGVVXH_hZAwkW8JUC4cVrCL4
$LENS airdrop is happening sooner than you can imagine. Next millionaries in making
As you know, **Zk-rollups** have recently become one of the most talked-about topics in the decentralized finance (DeFi) space. With Ethereum’s scaling limitations becoming increasingly apparent, many in the DeFi space have turned to Zk-rollups as a potential solution. But what exactly are Zk-rollups and why are they so interesting for DeFi researchers? A Zk-rollup is a Layer 2 scaling solution that allows for off-chain transactions to be bundled into a single on-chain transaction. This allows for much faster and cheaper transactions than would be possible on the Ethereum main chain. By using zk-SNARKs, a zero-knowledge proof system, Zk-rollups can ensure the privacy and security of the off-chain transactions. One of the key advantages of Zk-rollups is that they allow for the creation of decentralized exchanges (DEXs) with fast and low-cost transactions. This opens up new possibilities for DeFi applications, such as fast token swaps and low-cost lending platforms. Additionally, Zk-rollups allow for the creation of new DeFi products and services that were previously not possible due to the limitations of the Ethereum main chain. Another advantage of Zk-rollups is their ability to handle a large number of transactions. This makes them ideal for DeFi applications that require a large number of transactions, such as automated market maker (AMM) platforms. This also makes Zk-rollups a potentially useful solution for solving the scalability issues facing the Ethereum main chain. In addition to improving transaction throughput, zk-rollups also offer improved privacy compared to traditional Ethereum transactions. Because the transactions are bundled together, individual transactions are less likely to be singled out and linked to specific addresses. This can be important for individuals and organizations that require greater privacy in their transactions. While zk-rollups are often referred to as validity rollups, it is important to note that they offer much more than just a validity guarantee. The use of zero-knowledge proofs in zk-rollups enables a number of other benefits, including improved privacy and increased transaction throughput. For this reason, zk-rollups have become an increasingly popular solution for a wide range of use cases in the decentralized finance (DeFi) space, and are likely to become even more popular in the coming years as the technology continues to mature and evolve.
Let's GHOOOOOOO! We are live on Testnet! 👻 gho.xyz Stay up to date on all things GHO here (and grab the genesis edition collect!)
**Few Tips for Writing Secure and Efficient Smart Contracts in Solidity** Smart contracts are self-executing contracts with the terms of the agreement between buyer and seller being directly written into lines of code. They are designed to facilitate, verify, and enforce the negotiation or performance of a contract. The Solidity programming language is a widely-used, contract-oriented language specifically tailored for the development of smart contracts on the Ethereum platform. *As a Solidity developer, it is important to prioritize both security and efficiency in your smart contract code. In this article, we’ll cover some key tips and best practices for writing secure and efficient smart contracts in Solidity.* Smart contracts are immutable, meaning that once they are deployed to the blockchain, their code cannot be changed. This means it is essential to thoroughly test and audit your smart contract code before deployment to ensure that it is free of errors and vulnerabilities. Here are a few common security pitfalls to avoid when writing Solidity smart contracts: **Insecure Libraries or Functions** It’s important to be cautious when using third-party libraries or functions in your smart contracts. These external dependencies can introduce vulnerabilities if they are not thoroughly tested or if they are not kept up to date with the latest security best practices. To minimize the risk of using insecure libraries or functions, it’s a good idea to perform thorough security reviews and testing on any external code that you plan to use in your contracts. You should also consider using verified libraries from reputable sources whenever possible. **Reentrancy Vulnerabilities** Reentrancy vulnerabilities occur when a contract calls an external contract that can call back into the original contract before the original call has completed. This can lead to unexpected and potentially malicious behavior, such as the manipulation of contract state or an infinite loop. To protect against reentrancy vulnerabilities, it’s a good idea to use the require function to ensure that certain conditions are met before executing important actions within your contract. You can also use the lock and unlock pattern to prevent reentrancy attacks by setting a flag when the contract is executing an important function and checking for that flag before allowing external calls to be made. Here’s an example of how to use the lock and unlock pattern in Solidity: `bool locked = false;` `function doImportantAction() public {` `require(!locked, "Contract is locked"); // Ensure the contract is not already locked` `locked = true; // Set the lock flag` `// Do important action here` `locked = false; // Clear the lock flag` `}` **Integer Overflow/Underflow** Integer overflow and underflow occur when a value is incremented or decremented beyond the maximum or minimum value that can be represented by the data type. This can lead to unexpected and potentially malicious behavior, such as the manipulation of contract state or the execution of unintended code. To protect against integer overflow/underflow vulnerabilities, it’s a good idea to use the SafeMath library, which provides a set of functions that automatically handle overflow/underflow checks for you. You can also use the require function to ensure that certain conditions are met before executing important actions within your contract. Here’s an example of how to use the SafeMath library in Solidity: `pragma solidity ^0.8.0;` `import "https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol";` `contract MyContract {` `using SafeMath for uint; // Use SafeMath for all uint operations` `uint public balance;` `function incrementBalance(uint amount) public {` `balance = balance.add(amount); // Use SafeMath's add function to handle overflow/underflow checks` `}` `}` **Use the Latest Version of Solidity** It’s important to keep your Solidity compiler up to date with the latest version to take advantage of the latest features and security improvements. You should also be sure to check the Solidity documentation regularly to stay up to date with the latest best practices and guidelines. **Best Practices for Writing Efficient Smart Contracts** *In addition to security, it’s important to consider efficiency when writing Solidity smart contracts. Gas is the execution fee for performing operations on the Ethereum network, and the amount of gas a contract consumes can affect its cost and speed.* To minimize gas consumption, it’s a good idea to minimize the number of function calls and data storage operations in your contract. You can also consider using cheaper alternatives for certain operations, such as using delete instead of pop for arrays. Here’s an example of how to minimize gas consumption by reducing the number of function calls: `pragma solidity ^0.8.0;` `contract MyContract {` `uint[] public values;` `function addValues(uint[] memory newValues) public {` `// Instead of calling push for each new value, use a loop to add all values at once` `for (uint i = 0; i < newValues.length; i++) {` `values.push(newValues[i]);` `}` `}` `}` **Avoid using loops** Loops can be expensive in terms of gas consumption, as they require multiple function calls to execute. If possible, try to use alternative methods that do not require looping, such as using a mapping or array with a fixed size. **Avoid using nested function calls** Nested function calls can also be expensive in terms of gas consumption, as they require multiple function calls to execute. Instead, consider using inline assembly or creating a separate contract for the nested function. **Use the view or pure function modifier when appropriate** The view and pure function modifiers allow a function to read data from the blockchain without modifying it, which can help reduce gas costs. Use these modifiers when appropriate to minimize gas usage. **Consider using a gas optimization tool** There are several tools available that can help you optimize your smart contract code for gas efficiency, such as Mythril, EthLint, and Oyente. These tools can help you identify potential gas optimization opportunities and suggest improvements. *Conclusion* In summary, it’s important to prioritize both security and efficiency when writing Solidity smart contracts. By thoroughly testing and auditing your code, avoiding common security pitfalls, and optimizing gas usage, you can create reliable and efficient smart contracts that meet the needs of your users.
solidity compiler Solidity compiler generates you two files - abi and bin. Check out video for further explanation #bytes
gm lens frens 👋 Today I have made an important decision in my life 📢 I quit my job today and going to focus full-time on maintaining the first-ever open-source frontend @lenster.lens 🌸 powered by @lensprotocol 🌿. Building social media was my dream since 10th grade, I built more than 4 social media in public but all failed, Lenster is my 5th one and it’s going crazy ⚡️. I believe building in public is key 🔑 to the success of a product. We have a lot of items queued up in the roadmap, be excited about it 🕺 **Collect this post for 2 WMATIC and support Lenster’s development 🙏**
Want a basic tutorial script on how to monitor Ethereum transactions using subscriptions ? Worry not, this might get you started - https://medium.com/@0xAnon101/monitor-any-ethereum-account-transaction-using-subscriptions-7874bea7c183 *Not meant to be used in production