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Documentation Index

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The Bark SDK is a set of libraries for building self-custodial bitcoin wallet apps. Keys stay on the user’s device, and your app talks directly to Ark servers. Use the Bark SDK when you’re building:
  • Mobile wallet apps
  • Desktop wallet apps
  • Browser-based wallet apps
  • Wallets for custom or embedded hardware
If you’re building bitcoin applications for server infrastructure, try Barkd.

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Pick your language

Each guide below walks you through installing the SDK, creating a wallet, and making your first payment, then links to the full library reference. Rust is the core implementation; the other languages are bindings around it.

Rust ★

Core library—most complete and performant

React Native

Cross-platform mobile apps with TypeScript
https://mintcdn.com/second-0659a37d/Jga8RruMCrHYBFjK/images/flutter-logo.svg?fit=max&auto=format&n=Jga8RruMCrHYBFjK&q=85&s=bee498642147e00f2206a49634670ca0

Flutter

Cross-platform mobile apps with Dart

Swift

Native iOS apps
https://mintcdn.com/second-0659a37d/IZIYL7kfKRS394NE/images/kotlin-logo.svg?fit=max&auto=format&n=IZIYL7kfKRS394NE&q=85&s=245b783dc45398d84ab7541d4afdeeda

Kotlin

Native Android apps
https://mintcdn.com/second-0659a37d/Jga8RruMCrHYBFjK/images/go-logo.svg?fit=max&auto=format&n=Jga8RruMCrHYBFjK&q=85&s=b4540176ae0d16a8df1ba3998d222ec2

Go

Native Go bindings

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How it works

The Bark SDK uses UniFFI bindings to run the core Rust library directly in your app. Everything happens on-device:
  • Keys stay on the device: The user’s private keys are generated and stored locally.
  • Direct protocol access: Your app communicates directly with Ark servers.
  • No backend required: You don’t need to run any server infrastructure.
Wallet recovery is not yet implemented, so backups are critical. Make sure your app backs up wallet data to iCloud, Google Drive, or another secure location.