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How to write an Ethereum Smart contract from scratch? : Expert take

How to write an Ethereum Smart contract from scratch?
How to write an Ethereum Smart contract from scratch?

How to write an Ethereum Smart contract from scratch? : Expert take

If you have gone through the basics of Ethereum and how the whole things work, you would of course be interested in knowing how the smart contracts are built. One of the most sought after feature of Ethereum is a smart contract and more and more people are looking to build and work with these decentralized applications or dApps. Of course this is a whole another new dimension that people are being introduced to and without any preparation beforehand, plunging yourself straight into the technical depths of this space can be quite daunting.

To help you with getting started on how to simply write an Ethereum smart contract from scratch, here is a little guide to help you by. Since it is always wise to take baby steps while learning something new, we would not be focussing much on deploying the app and testing it but simply how to get started with writing one.

Before we get started, let us have a quick recap and remember what a smart contract exactly is. It is simply a computer protocol that has been codified to enforce the negotiation of a contract on the Ethereum platform.

If you have absolutely no experience with programming, you might face a little difficulty getting on board with writing a smart contract. We first recommend gaining some basic knowledge about coding so that you can ease into your journey of writing a smart contract.

Decide on the business logic

Since a smart contract is used to basically implement a business logic, decide on what you want your smart contract to be doing. A vague idea would not help you. You need to know and identify exactly what you want your smart contract to do for you. Do you want to use it in a casino? Do you want to build it for a marketplace? It could be about anything and everything but you need to have a very clear picture in mind. A solid idea.

Learn Solidity for ethereum smart contract

Once the business logic or creative thinking part of this endeavor is done and decided, all you are left with is the technical part. The very first step for you to walk upon is to learn Solidity. The Ethereum Virtual Machine works on this programming language. Its structure is very similar to Javascript and C++ and once you have carefully gone through its documentation and learnt the syntax of this language and understood how to write a code in Solidity, you should proceed ahead to get your hands at the required toolkit to completely work your smart contract on. You could learn Solidity from several books like Solidity Programming Essentials: A beginner’s guide to build smart contracts for Ethereum and blockchain, Introducing Ethereum and Solidity: Foundations of Cryptocurrency and Blockchain Programming for Beginners, Ethereum Smart Contract Development: Build blockchain-based decentralized applications using Solidity. You could also access the official Solidity guide by Ethereum at this link.

Some basic tools for ethereum smart contract

Now which of all the given tools you would require for your smart contract depends on the business logic you wish to build however these are the tools which almost all of them need.

The very first thing you would need is a tool named Truffle. You can access it on Github at this link. Truffle is basically a development framework for Ethereum in which you would code your business logic using the programming language Solidity. Next you would need to get your hands on Node.js, a runtime environment to write your tests and deploy them. Now for greater efficiency you would need something that would manage your accounts and tokens and that is just what Parity does which is a fast and much more secure Ethereum client than any other available out there. The last must have tool on this list would be Web3.js. You would of course require something that would bridge the gap between your laptop and the Ethereum network. Web3.js does just that by making a communication protocol with the Ethereum network using a Javascript API.

Write the ethereum smart contract

Retract a step back from starting to write your smart contract and first write an applicable automated unit test of your business logic in Javascript or even Solidity itself. This would be used to test your smart contract against and see if it actually works correctly or not.

Once you have good practical and working knowledge of how to code in Solidity and you have set up all the others tools on your laptop like Truffle, Node.js, Parity and Web3.js, you can now begin to code your own smart contract, finally. Since you had already set out the business logic you would want your smart contract to work on, you need not brainstorm now. All you have to do is use your knowledge and understanding of Solidity and code your business logic by implementing it in Truffle using the Solidity language.

Testing and deploying

Once your business contract is codified and ready, test it against the automated unit test. I fit throws an error, fix it, if it does not, move onto the next step of deployment. Compile your tested smart contract in Truffle and deploy your smart contract on the original Ethereum network or on the Ropsten testnet. Both these options would require some sort of gas to pay for the processing.

Follow these simple steps, and although this might take a little more time than you would like, remember, patience is virtuous and in the long run it would provide you great outputs.