Introduction

Archway is a blockchain that utilizes the CosmWasm engine to power its smart contracts. CosmWasm is a smart contract platform that uses WebAssembly (Wasm) to run contracts in a secure and efficient virtual machine and designed to enable multi-chain smart contracts.

What are smart contracts?

Smart contracts are self-executing programs stored on the Archway blockchain that run when predetermined conditions are met. On Archway, these contracts are built using the Rust programming language, known for its performance and safety features. Smart contracts form the basis of decentralized applications (dapps), enabling complex, automated interactions on the blockchain.

On Archway, smart contracts are possible through CosmWasm. CosmWasm is a smart contract platform written as a module that can be integrated into any blockchain built on top of the Cosmos SDK. In simple terms, it is the Cosmos (Cosm) way of utilizing WebAssembly (Wasm), hence its name.

How smart contracts operate

1. Automated Execution: Smart contracts automatically execute actions when specific conditions are met, without the need for intermediaries.
2. Flexible Mutability: Contracts on Archway can be designed as either mutable or immutable. Immutable contracts provide unchangeable logic, ensuring transparency and preventing tampering. Mutable contracts allow for upgrades, enabling developers to improve functionality over time while maintaining appropriate governance mechanisms.
3. Decentralized Storage: The contract and its state are stored across the blockchain network, making them resistant to single points of failure.
4. Deterministic Outcomes: Given the same input and state, a smart contract will always produce the same result, ensuring predictability.
5. Interaction via Transactions: Users interact with smart contracts by sending transactions to the contract's address on the blockchain.

Why smart contracts are useful

1. Trust and Transparency: Smart contracts remove the need for trusted intermediaries in many transactions, as their execution is transparent and verifiable.
2. Efficiency: By automating processes, smart contracts can significantly reduce transaction times and costs.
3. Accuracy: Smart contracts eliminate the errors that can occur in manually processed transactions.
4. Security: The decentralized nature of blockchain and the immutability of smart contracts provide a high level of security against fraud and tampering.
5. Programmable Money: Smart contracts enable complex financial instruments and agreements to be encoded directly into the blockchain.
6. Interoperability: In ecosystems like Cosmos, smart contracts can facilitate interactions between different blockchain networks.

Rust

Rust is the language used for developing smart contracts on Archway. Here’s why Rust is an excellent choice:

1. Memory Safety: Rust’s unique ownership model ensures memory safety without needing a garbage collector. This feature helps prevent common bugs and vulnerabilities, such as null pointer dereferencing and buffer overflows.
2. Performance: Rust provides performance on par with C and C++, making it ideal for blockchain applications where efficiency is critical.
3. Concurrency: Rust’s concurrency model allows for safe and efficient multi-threading, which is essential for handling the high transaction throughput required by blockchain networks.
4. Developer Experience: Rust’s syntax is modern and expressive, with a robust tooling ecosystem that includes features like Cargo (the Rust package manager), Rustfmt (code formatting), and Clippy (linting). These tools enhance the developer experience and productivity.
5. Active Community and Ecosystem: Rust has a growing and active community, which means continuous improvements and extensive libraries and frameworks that developers can leverage.

Learning resources for Rust

To help you get started with Rust, here are some valuable resources:

• The Rust Programming Language Book: This is the official book on Rust, often referred to as "The Rust Book." It's an excellent resource for learning Rust from scratch.
• Rust by Example: This resource offers a collection of runnable examples that cover various Rust concepts and standard libraries.
• Rustlings: An interactive tutorial that helps you learn Rust through small exercises.
• Rust Language Cheat Sheet: A handy reference guide for common Rust syntax and concepts.
• The Rust Programming Language Forum: A community forum where you can ask questions, share knowledge, and discuss Rust-related topics.
• Rust's Official YouTube Channel: Contains tutorials, talks, and other educational videos about Rust.

Additional resources

In addition to this documentation, there are also many valuable resources available to aid you in your CosmWasm journey. Some of these include:

• Area-52 is an excellent tutorial series focused on CosmWasm smart contract development.
• An array of example smart contracts to try out.
• Documentation for the core contract libraries.
• Documentation for the storage helpers.

We extend our gratitude to the Interchain Foundation for financing a significant portion of the development efforts that led to the production of CosmWasm.