> For the complete documentation index, see [llms.txt](https://docs.thorchain.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thorchain.org/technical-documentation/technology/cosmwasm.md).

# CosmWasm

THORChain now supports **CosmWasm smart contracts** directly on the base chain. This is called the **App Layer** and was introduced with SDK V50 (V3.0). Contracts are written in WebAssembly (Wasm), most commonly using [Rust](https://www.rust-lang.org/).

## How it works

* CosmWasm runs inside THORNode through the `x/wasm` module.
* Contracts are **permissioned**: only approved code and deployers can be whitelisted for mainnet.
* All contracts are tested on **stagenet** before release.
* Nodes can pause contracts or the entire app layer if needed (via Mimir).

## Supported assets

* **Native RUNE and L1 assets** (BTC, ETH, ATOM, etc.) can be used.
* **Secured Assets** (e.g. `btc-btc`) are wrapped forms of L1s managed in THORChain’s state.
* **TokenFactory assets** (“X assets”) can be created by contracts.

> Trade assets (deposit slips) are not supported as contract-moved tokens.

## Security model

The App Layer is **sandboxed** from the base layer:

* Contracts have no special privileges beyond a normal THOR address.
* They can send, swap, or call other contracts, but cannot touch vault logic.
* If an app fails, the base chain remains secure.

## Why it matters

* Developers can build DeFi apps directly on THORChain (orderbooks, perps, stablecoins, lending, etc.).
* Apps can share fees with THORNodes to pay for the security they use.
* Users interact with apps natively from L1 wallets — no wrapping or bridges.

## Learn more

* [THORChain Developer Documentation](https://dev.thorchain.org/)
* [CosmWasm Documentation](https://docs.cosmwasm.com/docs/)
* ADR-020: App Layer (full design and security details)