Bitcoin (BTC) is a cryptocurrency developed in 2009 by a modest developer under the name of Satoshi Nakamoto. Bitcoin was introduced for the first time in Satoshi’s white paper. It was envisioned as a decentralized digital currency, which means that it operates with no central authority (like a bank) in charge.

To achieve this, Bitcoin utilizes a special peer-to-peer technology known as blockchain technology. Moreover, Bitcoin is an open-source (free) software, i.e. its design is public, nobody owns and controls Bitcoin, and anyone can become a Bitcoin developer.

In this article, we’ll explain a little bit about cryptocurrency programming and present you with the most popular programming languages for developing cryptocurrencies. By the end of this guide, you’ll also learn what language Bitcoin is written in.

Let’s get started!

Word blockchain in tiles

How to Program Cryptocurrency and Blockchain

A cryptocurrency is a software written with the use of a programming language. There are a number of different types of programming languages that one can use. Your choice largely depends on the type of coin you want to create, the features it should have, its functionalities and purpose, as well as the type of cryptographic algorithm you’ll use (e.g. Proof of Work, Proof of Stake, or a hybrid of both), etc.

Theoretically, you can use any programming language to create a cryptocurrency. However, the most common languages for creating cryptocurrencies are C, C++, Java, Python, and Perl. Cryptocurrencies are open-source software, which means that anyone can access their programming scripts. This allows developers to use the code and build their alternate coins (altcoins).

Developing and maintaining a public blockchain is not an easy task, for a number of reasons:

  • Security: The blockchain should be very secure – otherwise, any programmer can hack the ledger and get away with potentially millions of dollars. So, in order to prevent this and achieve better security, blockchain development takes more time.
  • Resources Management: You have to keep up with all the network demands.
  • Performance: In order for blockchain to perform at its highest possible capabilities, you have to choose a programming language with a versatile nature.
  • Isolation: In blockchain development, all transaction operations must be deterministic. You cannot have a transaction that behaves one way in one instance and then behaves another way in a second instance. In order to solve this problem, the developers have to obtain an Isolation mechanism, i.e. a mechanism that makes it possible to isolate your transactions and smart contracts from non-deterministic elements.

Here are some key aspects to keep in mind when dealing with the aforementioned challenges:

  • Your blockchain should be available and secure for anyone to access.
  • You should obtain the necessary resources for handling queries and keeping up with the maintenance demands of a cryptocurrency network.
  • You’ll have to be able to complete tasks such as digital signature verification as transactions need to be well thought out in order to create an efficient platform.
  • You have to pay attention to the performance of the currency’s platform and the cryptocurrency itself.

The Best Programming Languages for Cryptocurrency and Blockchain

You can develop a cryptocurrency by using only one or multiple programming languages. Let’s take a look at some of the best programming languages for writing cryptocurrencies and blockchains:

C++

C++ is one of the most popular programming languages in the blockchain industry. It’s an object-oriented language and because of that, it’s perfect for blockchain development. C++ uses principles such as abstraction, data hiding, polymorphism, and encapsulation to prevent inadvertent data edits on the blockchain. Its memory control capabilities are another thing that attracts blockchain developers to use C++.

This language helps keep blocks secure while managing a large number of resource requests by allowing each network node to reject or accept individual blocks. C++ offers an easy way of handling parallel tasks and advanced multi-trading. This is why Bitcoin, Ripple, Litecoin, EOS, etc. are all developed in C++.

Python

Like C++, Python is also an object-oriented language. Some of the advantages and functionalities of Python are:

  • It doesn’t have a steep learning curve.
  • It offers access to dynamic architecture.
  • It’s perfect for both base and scripting approaches.
  • It has open-source support.
  • It’s efficient for prototyping, etc.

The only problem with Python is that it’s an interpreted language and not a compiled one, which can create problems when designing complex cryptographic operations on the blockchain. Blockchains such as Ethereum, Steem, and NEO are developed using Python.

Java

The Java software development language was derived from C-syntax and is widely chosen for developing sophisticated smart contracts. Java has an Application Programming Interface (API) that is useful if you want to develop an application without knowing the inside implementation. The programs developed in Java can be transferred on other platforms or run on any computer as long as it has installed Java Runtime Environment (JRE). Some popular blockchains that use Java are Ethereum, IOTA, and NEO.

Solidity

Solidity is a programming language for blockchain and smart contract development that has been designed by Ethereum developers for developing Ethereum-based solutions. The domain language uses many of the same syntax and principles as JavaScript, Powershell, and C++ in order to develop high-quality, decentralized applications. Solidity was created for writing smart contracts that run on the Ethereum Virtual Machine (EVM).

Some of the features and functionality of Solidity are:

  • Developer-friendliness;
  • Statically typed programming;
  • Accuracy;
  • Possibility of inheritance properties in smart contracts;
  • Accessibility to JavaScript debuggers, infrastructure, and other tools.

JavaScript

JavaScript is quite popular with blockchain programmers as it allows them to build highly capable and creative blockchain applications. The fact that every web system already uses JavaScript in some capacity is a big advantage that JavaScript has over other languages. This way, developers don’t have to worry about language integration and can focus on the application logic for the blockchain instead.

PHP

PHP is another programming language recommended for creating and developing blockchain solutions of different complexity ranges. PHP has a huge open-source community and object-oriented features.

Golang

Golang or GO language is a new programming language developed by Google. It’s an open-source general programming language loosely based on the syntax of the C programming language. Some of the popular blockchains developed using GO are the Ethereum blockchains, Dero, Hyperledger Fabric, and GoChain.

What Language Is Bitcoin Core Written In?

Bitcoin Core (Bitcoin-Qt) is a security software that is programmed to resolve which blockchain contents are considered to be valid transactions. This software helps protect digital assets worth a large amount of money, so every change of code needs to be rewired by experienced developers. 

Bitcoin Core users accept only the valid transactions to enter the blockchain. Because of the feasibility of the system, users in general and even new crypto creators very often prefer using the Bitcoin blockchain as a basis for a new network.

The most significant features of the Bitcoin Core are:

  • Full Validation: Bitcoin Core ensures every block and every transaction it accepts is valid.
  • Better privacy: Bitcoin Core provides exclusive privacy features that make it even harder for anyone to track your transactions.
  • A better user interface: The Bitcoin Core wallet has better features and interface than most crypto wallets.
  • Support the network: Bitcoin Core supports other peers and it can donate bandwidth to less well-connected users.

The reference implementation of Bitcoin Core has mostly been written in C++ by Satoshi Nakamoto. C++ is a programming language introduced in 1985 by Bjarne Stroustrup and is considered to be the best programming language for cryptocurrency development. 

However,  the creator, as he explained in a recent podcast interview, doesn’t like that Bitcoin was written in his programming language. This is mostly because he believes that mining Bitcoin consumes too much energy (with various studies outlining how it’s bad for the environment) and fears that cryptocurrencies might be used for criminal activities.

There are several reasons why Satoshi Nakamoto chose to write the Bitcoin Core code in C++:

  • C++ is the language of choice for high-performance applications because it allows for so much optimization. 
  • A system like Bitcoin has extremely strong requirements about consistency in behavior.
  • C++ has been around for a long time and it has been upgrading consistently. It’s a highly reliable and well-tested language.
  • C++ is a relatively low-level programming language with little abstraction from the hardware, which means the programmer is the one that has to handle memory management. This gives the programmer an extremely high level of control.

The next implementations in the Bitcoin Core code are developed in different programming languages such as Python, Java, and GO.

What Language Is the Bitcoin Blockchain Written In?

Blockchain is the foundational data structure behind Bitcoin. A blockchain is a chain of recorded data called blocks. In the Bitcoin network, each block contains several Bitcoin transactions and they’re all “chained” together using a cryptographic technique called hashing. This technique ensures that the block cannot be reordered or changed after it’s added to the blockchain.

The Bitcoin blockchain has three important features:

  • Transparency.

The Bitcoin blockchain is a completely public ledger. Moreover, anyone with an internet connection can access it and see which addresses own Bitcoin (but not the people behind those addresses). Transparency is essential because, without it, it would be impossible to verify the circulating supply of bitcoins or audit the validity of the Bitcoin transactions on the Bitcoin network.

  • Decentralization.

Bitcoin’s blockchain is distributed. This means that the blockchain is maintained and stored on tens of thousands of computers around the world. This is why Bitcoin’s codebase is open source and anyone can download a copy of it from GitHub

  • Immutability.

This means that the Bitcoin blockchain has the ability to remain unchanged.  

Bitcoin blockchains can be developed or created in different programming languages, such as C++, Java, and Python. So you have multiple options of programming languages for developing Bitcoin blockchains. It’s up to you which one you’ll choose, but it still depends on the blockchain you want to create.

Bitcoin Script

Nowadays, smart contracts have become a big part of every cryptocurrency ecosystem. Unlike Ethereum, the Bitcoin blockchain cannot create smart contracts on its own, so Satoshi Nakamoto developed another programming language only for this purpose named Bitcoin Script.

Many people think that Bitcoin is unable to execute smart contracts, but thanks to Bitcoin Script, this is no longer true. Its capabilities are limited compared to what you can do on Ethereum.

Bitcoin Script is a simple programming language used for the processing of transactions. It’s based on a series of linear structures known as stack. This language is not Full Turing because its functionality is limited and it doesn’t have loops.

The main purpose of developing a Bitcoin Script language is to provide a set of flexible and easy parameters to allow a transaction. During the development of Bitcoin, Satoshi Nakamoto disabled numerous existing functions, and one of them is multiplication. So, this script programming language decides if an operation can or cannot be fulfilled. Bitcoin Script prevents making errors in the system and the unnecessary use of very complex transactions. 

A Few Words Before You Go…

We hope that this article succeeded in giving you some clue about the programming languages that developers use to create and develop new digital currencies and blockchains. Finally, you know what Bitcoin Core is and what programming language it’s written in. Who knows, maybe this article will inspire you to try your hand at developing a cryptocurrency yourself.