Other types of blockchain programmers

This chapter intended to give you an intuitive understanding of how blockchain works. However, it's not a complete scope of how it works. My explanation differs quite a lot from how Bitcoin works (and even Ethereum). Ethereum does not use SHA-256 for hashing; it commonly uses the Keccak-256 algorithm. In our case, we only put one history/transaction/payload in one block, but Bitcoin can save more than 1,000 transactions in one block. Then, we generate a private key and public key by using RSA cryptography, while Bitcoin and Ethereum use elliptic curve cryptography. In our case, the payload is history (who likes/loves/hates an animal), but in Bitcoin it's a transaction that has a dependency on the previous payload. In Ethereum itself, it's a state of programs. So, if you have variable a as equal to integer 5 in the payload, it could be something like change variable a to integer 7. In the Bitcoin consensus, we choose the blockchain that has the most hashing rate power, not the one that has the longest chain. For example, blockchain A has two blocks, but each block has the answer to solve the puzzle with 12 leading zeros, while blockchain B has ten blocks but each block has the answer to solving the puzzle with only five leading zeros. In this situation, blockchain A has the most hash rate power.

Now, we go back to the following questions: what does it mean to be a blockchain programmer? How many types of Blockchain programmers are there? What is the scope of this book?

Blockchain programming could mean that you are working on improving the state of Bitcoin or creating a fork of Bitcoin, such as Bitcoin Cash. You need C++ and Python. If you are creating a Bitcoin fork, such as Bitcoin Gold, you need to dig deeper into cryptography. In Bitcoin Gold, the developers changed the proof of work hashing function from SHA-256 to Equihash because Equihash is ASIC resistant. ASIC resistance means you cannot create a specific machine to do the hashing. You need a computer with a GPU to do the Equihash hashing function, but this book will not discuss that.

Furthermore, Blockchain programming could mean that you are working on improving the Ethereum Virtual Machine. You need Go, C++, or Python. You need to understand how to interact with low-level cryptographic library functions. An intuitive understanding of how basic cryptography works is not enough, but this book will not discuss that either.

Blockchain programming could mean that you are writing the program on top of Ethereum. You need Solidity or Vyper for this, which this book will discuss. You only need an intuitive understanding of how basic cryptography works. You have been abstracted away from low-level cryptography. Once in a while, you might use a hashing function in a program you write, but nothing fancy.

Blockchain programming could mean that you are writing a program to interact with the program on top of Ethereum, which sounds meta. But what you will need for this depends on the platform. If it is a mobile app, you need Kotlin, Java, Swift, Obj-C, or even C++. If it is a web frontend, you will most likely need JavaScript. Only an intuitive understanding of how basic cryptography works is needed. This book will discuss some of this.

This is the same as if I asked you, what does it entail when someone wants to become a web developer? The answer is quite diverse. Should I learn Ruby, Java, PHP, or Python? Should I learn Ruby on Rails, Laravel, or Django?

This book is going to teach you how to build a program on top of Ethereum (not to be confused with building Ethereum itself). Comparing this with web development, this is like saying that this book is going to teach you how to build a web application using Ruby on Rails, but the book does not teach you how to dissect the Ruby on Rails framework itself. This does not mean that the internals of Ruby on Rails are not important, it just means that most of the time, you don't need them.

This book will teach you to use the Python programming language, assuming that you have basic knowledge of Python already. But why Python? The answer is a cliché: Python is one of the easiest and most popular programming languages. It lowers the barrier to entry for someone who wants to jump into blockchain.