Web Assembly (WASM)

Web Assembly is a binary code format that allows complex applications to be run in web browsers and virtual machines at near-native speeds.

What Is Web Assembly?

Web Assembly, abbreviated as WASM, is an open-source technology that employs a compact binary code instruction format to compile and execute code on web browsers or a virtual machine (VM) like the Ethereum Virtual Machine (EVM). 

The concept of WASM as a new binary format was introduced in 2015 as a collaborative effort between major browser providers, including Mozilla, Google, Microsoft, and Apple. The group first released it in March 2017 to address performance limitations while enabling complex applications such as music streaming, computer-aided design (CAD), and video games to operate on the web seamlessly.

Simply put, WASM is a portable compilation target for high-level programming languages, such as JavaScript, C++, and Rust. This means that it can compile multiple programming languages into a single code standard that can operate at near-native speed in browsers and non-web environments. Therefore, WASM can serve as a capable alternative or complement to JavaScript. WASM also allows programmers to utilize or modify its source code. 

How Does WASM Work in Blockchains?

Developers can use WASM to create smart contracts or even develop decentralized applications (dApps). While smart contracts are typically written in high-level programming languages, such as Rust and Solidity, their source codes can be compiled into WASM bytecode. The resulting bytecode – which is a more efficient and compact version of the original code – is then deployed on a WASM-compatible protocol. 

Here’s how it works:

1. Write the source code – The developer authors the smart contract using a programming language of their choice. 
2. Compile – Convert the source code into a WASM bytecode using a WASM-compatible compiler such as Emscripten. 
3. Deploy – The WASM module is then uploaded to the blockchain network, which translates the bytecode into machine code. This machine code can be executed by the underlying blockchain, meaning that the WASM module can be invoked by transactions.

Examples of blockchains using WASM to write and execute smart contracts include Cosmos, Polkadot, and MultiversX.

Benefits of Using WASM in Blockchains

WASM’s low-level bytecode design facilitates fast and efficient execution across varying environments, making it ideal for blockchain protocols where speed is crucial. This high performance enables high transaction throughput, as well as complex computations, within blockchain virtual machines.

In addition, its language flexibility enables Web3 developers to create smart contracts in the programming languages of their choice. Expanding the language options for blockchain development encourages more developers to contribute to blockchain projects.

WASM also enhances blockchain security by providing additional features such as memory isolation and sandboxing. These features ensure the secure execution of smart contracts and dApps, typically maintaining the integrity and reliability of the blockchain network.

What’s more, WASM code is executable on web browsers, embedded devices, servers, or any other platform that supports it. This means that you can easily adapt and execute code written for blockchain virtual machines across different platforms, thereby increasing the scope and flexibility of blockchain applications.