> For the complete documentation index, see [llms.txt](https://gl-docs.gitbook.io/zkpass/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gl-docs.gitbook.io/zkpass/zkpass-developers-guide/zkpass-modules/dvr/dvr-client-roles/data-issuer.md).

# Data Issuer

The Data Issuer only needs to follow this step for integration with the zkPass Service:

* [<mark style="color:blue;">Providing REST API for user data retrieval</mark>](/zkpass/zkpass-developers-guide/zkpass-modules/dvr/dvr-client-roles/data-issuer/providing-user-data-retrieval-api.md)

## <mark style="color:blue;">Sample Implementation</mark>

Sample codes for the Data Issuer implementation follow. Each step is explained in detail in the subsections. The code is also available on the zkpass-sdk repo, as shown here:

{% @github-files/github-code-block url="<https://github.com/gl-zkPass/zkpass-sdk/blob/main/rust/zkpass-demo/src/data_issuer.rs>" %}