> For the complete documentation index, see [llms.txt](https://niftsy-protocol-niftsy-1.gitbook.io/niftsy/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://niftsy-protocol-niftsy-1.gitbook.io/niftsy/tutorials/dapps/cross-nft/version-0.md).

# Version 0

**App addresses:**

<https://app.envelop.is/crossings>

**Work chains**

| Type of chain | List of chains         |
| ------------- | ---------------------- |
| Testnet       | Goerli                 |
| Mainnet       | Ethereum, BSC, Polygon |