> For the complete documentation index, see [llms.txt](https://docs.ternoa.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ternoa.network/learn/ternoa-wasm-chain/ink-smart-contracts.md).

# ink! Smart contracts

With ink! you can write smart contracts in Rust for blockchains built on the Substrate framework.

## Why Rust is an ideal smart-contract language?

It is type-safe, memory-safe, and free of undefined behaviors. It generates small binaries because it doesn’t include extra bloat, like a garbage collector, and advanced optimizations and tree shaking remove dead code. Through compiler flags, Rust can automatically protect against integer overflow.

* **Rust ecosystem:** You gain from all of the support available to the Rust ecosystem for free. As the language develops, new features and functionality will improve how you can write smart contracts in the future.
* **Tooling:** Tools like rustfmt, clippy and rust-analyzer already work out of the box. The same goes for code formatting and syntax highlighting in most modern text editors. Also, Rust has an integrated test and benchmark runner,
* **No overhead:** Minimal runtime.
* **Safe & Efficient:** Zero-cost & safe abstractions.
* **Productive:** Cargo + crates.io Ecosystem.
* **1st class Wasm:** Rust provides the first class support for the WebAssembly.
* **Small Size:** In the space-constrained blockchain world size is important. The Rust compiler is a great help for that since it reorders struct fields to make each type as small as possible. Thus Rust data structures are very compact, in many cases even more compact than in C.


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