As humanity moves towards digitalization of everything, basic coding becomes essential even for the average non-techie person. This requirement is even more obvious when it comes to the blockchain sphere. If we’re really going for true decentralization, we all need to understand that things work at least on a basic level. Whether you’re an experienced software engineer or an average Joe, the first thing you need to do before learning how blockchain works is choosing a programming language.
For a new, booming technology developing at a breakneck pace, that programming language can be daunting. There are tons of them available, and different startups and open source communities have chosen different languages to build their products because of their different focus and desired feature sets. There is no standard and at this time; the choice would pretty much come down to your personal criteria and the type of applications you want.
In this article, we will review the most popular programming languages used in blockchain development to help you choose the most suitable option. Don’t delay any longer and go deep down the rabbit hole!
The most popular programming languages in blockchain
First, we need to understand which programming languages are best used when writing code on the blockchain. You’ll probably see some familiar names on this list.
C++
To review the language of blockchain programming, we have to look at their grandfather – C ++. This language was released in 1985 by Bjarne Stroustrup to make the original C more flexible. More than three decades later, it was used to build Bitcoin.
Unlike the original C, which is process-oriented, C++ is object-oriented. This approach makes C++ more time efficient when writing code. The data together with the functions are stored in so-called objects, which can be used later in other programs.
Due to its maturity, it is not surprising that featurewise C++ is quite robust when it comes to blockchain development. This language has memory management that ensures speed through efficient CPU management, threads that run parallel / non-parallel tasks at the same time, move semantics for convenient copying of data, compile-time polymorphism for better performance through division of responsibilities, and code isolation to separate data structures. In addition, its user base consists of more than four million developers.
One of the main disadvantages of C++ for blockchain developers is that it is not smart contract ready. This doesn’t mean you can’t code a smart contract in C++, just that some tweaks need to be made. This is why blockchain-specific languages have started to emerge.
Advantages: independent and cross-platform, high speed, similar to C
Cons: quite difficult to master, complex and sometimes difficult to debug, no garbage collection
Best for: Advanced users, understanding the fundamentals of Bitcoin
C#
C# is younger than C++, but also quite old. Created at the end of the 90s, within Microsoft, it quickly gained traction in the development community. It is an OOP (Object Oriented Programming) language that provides great services for enterprise-level application, cloud and cross-platform development. Supported largely by Microsoft, this language is a convenient tool for both professionals and casual coders.
Not only is C# flexible and easy to understand if you know C++ or Java, it also has many features. In addition to some C++ functionality, C# offers the .NET framework & class library, common language runtime, and development frameworks (such as WPF, XAML, and ASP.NET).
C# is favored by the big players in blockchain for a few reasons:
Its syntax is easy to understand for the majority of developers who already know C++ (4.4 million developments).
It is open source.
Allows you to write portable code for mobile devices.
It is affordable because of the BizSpark program.
Some of the most prominent startups basing their code on C# include NEO and Stratis. Also, C# has a separate Bitcoin framework (NBitcoin). Microsoft does not lag behind and presents the Azure platform vNext blockchain.
Advantages: object-oriented, strongly typed, dynamic code support
Cons: poor Linux support
Best suited for: building infrastructure blockchains, for Windows users
JavaScript
It is perhaps by far the most recognized programming language in the world. The websites you scroll through every day use javascript for a trendy look and advanced functionality. In 2007, Jeff Atwood created a law:
“Any application that can be written in JavaScript ends up being written in JavaScript.”
JavaScript is an OOP language that is easy to learn yet versatile. Using JS, developers can code clients & servers, IoT devices, and machine learning. One of the main advantages of JavaScript from a blockchain point of view is the asynchronous execution of events, that is, it allows nodes to communicate freely and efficiently. Another strength of JS is that it does not require compilation. However, simplicity comes at a cost. For all its features, JS is far from C++, but it is a great language for beginners.
JavaScript was not very popular among blockchain developers until the 2017 ICO breakout. CoinMarketCap currently has several high-profile startups based on this language, such as Lisk, Ark, and Nimiq. One of Ethereum’s most significant competitors, Tron, also supports JavaScript.
Advantages: Object-oriented, prototype-based, supports functional programming
Disadvantages: Dynamic, poorly typed
Best suited for: Entering the blockchain space, building dApps
Python
Python was created in a minimalist way. Therefore, this language is extremely easy to learn and a great entry point for beginners. It was created in 1991 and served a lot of purposes like application development, network server development, IoT and others. It may not be as recognized as JS yet, but it’s certainly gaining more momentum in the tech world.
Python is an OOP language. A joy to code and universal. A simple blockchain will require up to 50 lines to encode. Once the code is written, it can be run on multiple devices with different operating systems. There is also a huge library of frameworks such as Tensorflow and Django, although their documentation can be lacking in some cases. It should be added that there are currently special libraries that deal with the development of the blockchain. Like JavaScript, Python does not require compilation, although it can be compiled like C# and C++. Combine it with the accompanying dedicated testing environment and you have a Swiss army knife for your blockchain journey.
Python has been recognized by industry superstars. IBM Hyperledger implemented it in Sawtooth, and Ethereum created its own iteration of this language: Pyethereum.
Pros: Very easy to learn, pre-made libraries and frameworks, efficient
Disadvantages: Mostly used as a server language, not in such a smart context
Best for: Building dApps for beginners
It’s going
Golang (or Go) is an open source language derived from C. It is a very young language started in 2007 by Google developers. The implementation of the syntax is more Python-like – simplified to ensure efficiency and future-proof projects built with it.
Go’s strengths in blockchain programming include the availability of modular programming that makes the development process flexible, convenient testing tools, and a huge library of features. It would be most attractive to cloud computing developers as distributed computing is very easy for this language. Although this language requires compilation, it is a good factor for safety as all errors must be shown to the person writing the code before deployment. In addition, parallel programming with Goroutines increases the throughput of code and applications. This is crucial for scalability, which is a pain point in the blockchain space today. Finally, Go runs with the OS, not on top of it. This eliminates extra steps when creating EVMs, thereby increasing speed.
Go is a well-known language in the blockchain world. Consider IBM Hyperledger, which uses Golang to code smart contracts on its fabric. Docker is not a blockchain startup, but it works with distributed systems and is built with Go.
Advantages: Memory safety, garbage collection, strongly typed
Disadvantages: It is not so easy to learn, the community is relatively small, there are few packages
Best for: Building cloud dApps
Strength
Firmness is as young as Golang. Published in 2014 by Christian Reitwiessner and his team. It is a language created for writing smart contracts on Ethereum, which is why it is the most popular in the Ethereum ecosystem. It is worth noting that the ecosystem has grown hundreds of times over the past two years due to various startups flooding the market. As a result, Solidity has a large user base. Its standard (ERC20) has become a staple of the industry.
Solidity is an OOP and contact-oriented language. It is also Turing complete, meaning it can interpret various data management rules. Strength’s syntax is similar to JavaScript, but also has some similarities to C++ & Python. Despite its early stage, Solidity is a functional language, provides inheritance, various libraries, etc.
Currently, Solidity’s main use cases are EVM and smart contracts. It’s not much, but they’re extremely important and as blockchain-specific as you can get. If you want to build a dApp, then Solidity is your choice.
Advantages: Statically typed, easy to learn, trendy
Disadvantages: Not universal, vulnerable
Best suited for: Development of smart contracts
Basics of blockchain coding
Now that we’ve covered the most popular blockchain programming languages, it’s time to get down and dirty with the actual coding. Let’s see how basic operations are performed through different programming languages.
Before we get started, it’s a good idea to brush up on what blockchain is. A blockchain is a distributed ledger whose transactions are stored in a chain of blocks. A block is a placeholder for transaction records. Each new block has a pointer to the previous one in the form of a hash function. Once the block is full, a hash is created using all transactions and attached to it. There is also a timestamp server to prevent duplicate releases and a consensus mechanism to allow nodes to agree on the correct version of the ledger.
It’s time to put theory into practice. The purpose of this is not to create a complete application, but to show what the process looks like.
C++
Every blockchain has a hard-coded initial block, called a genesis block. Let’s create one.
C++ genesis blocks Image: Utoday
Now we can create another block. To do this, we type getLatestBlock ().
C++ adds blocks Image: Utoday
C++ consensusImage: Utoday
The consensus mechanism is a simple “for” loop function that covers all blocks, starting from 1, because there is no need to review genesis block 0.
C#
The C# blockchain data structure is quite simple. It has Block & Blockchain classes. Here they are.
C# blockImage: UtodayC# blockchainImage: Utoday
If we visualize the structure, it looks like this:
C# blockchain structureImage https://www.c-sharpcorner.com/
How to add new blocks:
C# add blocksImage: Utoday
In order for our blockchain to reach consensus, e.g. to validate it, we only need 2 lines of code along with an IsValid method that checks the data of each block and compares the hashes.
C# consensusImage: Utoday
JavaScript
Now we’re getting into the realms of more accessible languages, which should be more fun if you don’t have any coding experience. To create a blockchain, we need a runtime environment such as Node.js. Each of the additional blocks will have the following data: index, time of creation, misc (such as addresses of the sender & recipient and the amount transferred), hash of the previous block, own hash. Once that’s done, it’s time to move on to hardcoding the genesis block:
JavaScript genesis block Image: Utoday
Once we have obtained the genesis block, we now add blocks with new data via a nextBlock function. This function automatically loops through all 5 data types and includes them in each new block.
JavaScript Building Block Image: Utoday
Add JavaScript blocks Image: Utoday
Python
This time we’ll start by understanding what a transaction looks like in Python. This is a simple timestamped post with some data.
Python transactionImage: Utoday
These transactions are included in the blocks. Introducing this class.’
We will use SHA-256, which is used by Bitcoin to create hashes to verify the integrity of the blockchain.
Python hashImage: Utoday
Now we can add the blocks, but first let’s introduce the Proof-of-Work algorithm, which ensures that the blockchain data is not corrupted.
Python PoWImage: Utoday
Once this is done, we are clear to launch the blockchain.
It’s going
Let’s start by defining the properties of our blocks. BPM is arbitrary data such as network transactions, addresses, etc.
Golang block Image: Utoday
Blocks are created by extracting data into them and concatenating them with the appropriate results. The code for extracting the data in a Go block looks like this:
Finally, we can start making new blocks using the geneBlock function. Time to write the consensus represented by the isBlockValid function.
With everything set up, we are ready to start the block production process. Note that at this point the blockchain will need a server to run, so there are a few extra bits of code to reflect this.
Golang hashImage: Utoday
Strength
Building smart contracts is different from what we just reviewed, but it’s still simple. First we need to create a contract and name it. This contract is at the will of one person. In the event of their death, the funds must be automatically distributed to specific addresses.
Solidarity agreement Picture: Utoday
Here we enter the Ethereum address of the owner (owner), the amount left for distribution (unit) and the conditional variable of the owner’s state (bool). The next step is to add modifiers that extend the conditional logic to provide a function with the state of the owner.
In doing so, we can outline the titles that will receive the inheritance. We then proceed to specify the distribution of funds in case isDeceased = true. Please note that at this stage we can hide the function from the public by placing the “private” element next to the “payout” function. Voila, the code is ready to install.
Strength ModifiersImage: Utoday
Summary
In summary, there is no definitive blockchain-centric programming language. Blockchain itself is in its infancy and there are unexplored horizons and steps. As with many other fields, the best way to get around confidently is to become a full-fledged developer, which can be a difficult task given the amount of knowledge you’ll need. Fortunately, many programming languages have similarities in syntax and structure to ease the transition.
If you have to choose a language, you have to consider the context. If you want to focus on infrastructure projects, C++ and C# are better for you. In case you are more interested in developing applications on top of existing blockchains, JavaScript, Python and Go are good options to consider. If you just want to launch your own ERC20 token, Solidity will definitely cover your needs.
Also keep in mind that blockchains are language agnostic. With the integration of new languages, such as Simplicity, and existing languages, such as SQL, the lines between them are increasingly blurred. Remember that language is just a tool and you are free to use it for any purpose. Our best advice would be that if you already know a few languages, keep learning them – you will definitely be able to create blockchains with them. If you’re just starting out, try to find the easiest entry point – more towards JavaScript and Solidity.