> For the complete documentation index, see [llms.txt](https://docs.vanarchain.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vanarchain.com/builders/for-developers/build-with-thirdweb/engine.md).

# Engine

### Overview

Engine is an open-source, backend server that reads, writes, and deploys contracts at production scale.

### Why use Engine?

Engine enables your app to:

* Send multiple blockchain transactions at once.
* Resubmit stuck transactions, handling nonce values, gas settings, and RPC errors.
* Avoid duplicate transactions.
* Manage multiple backend wallets and their funds.
* Control access from your backends and team members.
* Sponsor user gas fees.
* Deploy and interact with smart accounts.
* Subscribe to contract events and transactions.

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="files"></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><strong>Engine</strong></td><td>Backend server to reliably call smart contracts</td><td><a href="/files/t6HroxC5El5MHgk10gSY">/files/t6HroxC5El5MHgk10gSY</a></td><td><a href="https://portal.thirdweb.com/infrastructure/engine/overview">https://portal.thirdweb.com/infrastructure/engine/overview</a></td></tr></tbody></table>