> For the complete documentation index, see [llms.txt](https://docs.onchainden.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.onchainden.com/creating-transactions/custom-transaction-builder.md).

# Custom Transaction Builder

Some teams like to directly interact with smart contracts and Den's transaction builder makes it easy with a Custom Transaction Builder, no matter how complicated your inputs are. This is accessible when you select the `Build it myself` option.

Paste in the address of the contract you'd like to interact with. Den will automatically retrieve the contract's ABI, and will even fetch ABIs for the proxy contract's implementations.

<figure><img src="/files/xq5V7L9Nh3oug3U7CCaD" alt=""><figcaption></figcaption></figure>


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