Yos Riady optimize for learning

👋 Hi, I'm Yos.

I'm a Software Engineer based in Singapore ☀️

Here are my recent thoughts...

Easy, Instant Mocks for Solidity Contracts

Easy, Instant Mocks for Solidity Contracts

In a previous post, we learned about forking mainnet as an alternative to mock contracts in Solidity. The major drawback with mock contracts is that you need to spend time to rewrite existing smart contracts as mocks. To get exhaustive mock coverage, you’ll end up rewriting whole protocols for the sake of testing.

What if there’s a magical way to mock contract functionality without writing mock contracts? Read on to learn more.

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Real World Contract Development with Forked Mainnet

Real World Contract Development with Forked Mainnet

Ethereum and other permissionless blockchains are innovation machines. Developers are free to build with completely public building blocks, stitching them together to create sophisticated systems out in the open.

When building a protocol of your own (DeFi, NFTs, etc), you’ll quickly realize that you need to interface with existing contracts. In a single transaction, your contracts may call several others. These contracts may include DeFi lending protocols, AMM pools, and marketplace contracts that are live on mainnet.

Interfacing with other protocols is a key part of smart contract development. But how do you develop against these building blocks?

Let’s hunt for an answer.

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Gas Efficient Tips to Optimize Storage in Solidity

Gas Efficient Tips to Optimize Storage Layout in Solidity

Computations on Ethereum cost gas. If you’re not careful, you may end up writing contracts that cost more than they should. High gas costs kill usability!

A common cause for high gas costs is an inefficient storage layout in Solidity contracts. In this post, let’s look at some tips you can use to help you write more gas-efficient contracts.

Read on to learn more!

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Recently

Recently

Recently is a periodic retrospective.

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Fault Tolerant Smart Contracts with Circuit Breakers

Fault Tolerant Smart Contracts with Circuit Breakers

Software systems are becoming more and more interconnected. Service-oriented architecture transforms software into smaller, independently deployable units that communicate over the network. APIs are eating the world, rapidly becoming the primary interface for business. Smart contracts go a step further - creating public, immutable protocols that anyone can run without permission.

Software is being broken down into and being offered as modular services. It’s innovation legos on steroids: By composing multiple building blocks together we can bootstrap new ventures much more rapidly at lower cost.

However, this new world of distributed systems introduces its own challenges. What happens if a service on a critical path fails? Can the system recover from faults? Or will a single failure cascade to downstream services in a catastrophic explosion of fire and death?

In the world of smart contracts, faults can be an extraordinarily expensive affair. With DeFi continuing to grow - can we do better, somehow?

In an ultra-interconnected system, fault tolerance is key. The COVID-19 pandemic showed everyone the importance of resiliency in the real world. A fault-tolerant design enables a system to continue its intended operation, possibly at a reduced level, rather than failing completely, when some part of the system fails.

In this article, we’ll explore:

  • The dangers of cascading failure in service oriented architectures,
  • Fault tolerance and resiliency patterns,
  • How circuit breakers can improve fault tolerance in smart contracts, and
  • An implementation of a Circuit Breaker in Solidity.
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Testing Smart Contracts

Testing Smart Contracts

Unit testing is a critical part of smart contract development. The high stakes and rigid immutability of smart contracts demands even more emphasis on testing compared to traditional software. Unit tests ensures your contracts are performing correctly at the most fundamental level, acting as a vanguard in your defense against bugs.

In this article, we’ll learn:

  • Why unit testing is important for smart contracts,
  • How to write unit tests for smart contracts,
  • How to use static types and Typescript to test smart contracts,
  • Helpful tools and utilities you can use for complex assertions,
  • Other smart contract testing best practices.

New (17 August): Typescript & Typechain support!

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Serverless Smart Contract Automation

Serverless Smart Contract Automation

‘Smart contracts’ is a misnomer. Despite its name, smart contracts on Ethereum are not self-executing digital agreements. Smart contract code only run when triggered by an external account. In other words, you need an external process to trigger the smart contract.

In this article, we’ll build a solution to this problem. You’ll learn:

  • Why you need off-chain smart contract automation
  • Use cases for smart contract automation
  • How to deploy serverless functions with the Serverless framework

Finally, we’ll go through serverless-ethers, a fully-functional smart contract automation service that you can run and deploy out-of-the box! Feel free to use this project as a base for building custom smart contract automation that fit your needs.

The serverless-ethers sample application is open source and available on Github. Just clone and hit deploy! 🚀

Read on to learn why we need automation and how it works.

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Recently

Recently

Recently is a periodic retrospective.

At the end of a month I publish a review of things I read/wrote/built/thought over the past month. My goal is to create a ‘brain log’ where I can capture these ideas on paper for future me to review.

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The Origin of Money

The Origin of Money

This is an abridged explanation of how money emerged from an initial state of barter. Most of the material is from the book Choice: Cooperation, Enterprise, and Human Action by Robert Murphy.

Murphy’s book reviews the works of Ludwig von Mises’ Human Action and Carl Menger’s On the Origins of Money. I highly recommend checking them out if you find the following summary interesting.

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The Ethics of Money Production

The Ethics of Money Production, Abridged

This is an abridged version of Jörg Guido Hülsmann’s The Ethics of Money Production, with an emphasis on the origins of money, private coinage, and competition of private currencies.

The original book is available as a free PDF and on paperback. Images used are from Spice and Wolf by Keito Koume and Isuna Hasekura.

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