> For the complete documentation index, see [llms.txt](https://docs.threshold.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.threshold.network/app-development.md). # App Development - [tBTC SDK](https://docs.threshold.network/app-development/tbtc-sdk.md): Build with Bitcoin using Threshold's tBTC SDK - [Quickstart](https://docs.threshold.network/app-development/tbtc-sdk/quickstart.md) - [Architecture](https://docs.threshold.network/app-development/tbtc-sdk/architecture.md) - [Guides](https://docs.threshold.network/app-development/tbtc-sdk/guides.md) - [Initialize SDK](https://docs.threshold.network/app-development/tbtc-sdk/guides/initialize-sdk.md) - [Ethereum and Bitcoin mainnet](https://docs.threshold.network/app-development/tbtc-sdk/guides/initialize-sdk/ethereum-and-bitcoin-mainnet.md): This is the most common case when you want to use the SDK to interact with the tBTC bridge on Ethereum and Bitcoin mainnet. - [Ethereum and Bitcoin testnet](https://docs.threshold.network/app-development/tbtc-sdk/guides/initialize-sdk/ethereum-and-bitcoin-testnet.md): This is the case where you want to use the SDK to interact with the tBTC bridge on Ethereum and Bitcoin testnet. - [Crosschain](https://docs.threshold.network/app-development/tbtc-sdk/guides/initialize-sdk/crosschain.md): This mode of the SDK will initialize Ethereum, Bitcoin and an L2 to work with tBTC. Compatible with mainnet and testnet. - [Custom mode](https://docs.threshold.network/app-development/tbtc-sdk/guides/initialize-sdk/custom-mode.md): Apart from the opinionated initialization functions, the SDK provides a flexible TBTC.initializeCustom function for advanced users. - [Deposit and mint](https://docs.threshold.network/app-development/tbtc-sdk/guides/deposit-and-mint.md) - [Unmint and redeem](https://docs.threshold.network/app-development/tbtc-sdk/guides/unmint-and-redeem.md) - [tBTC Contracts API](https://docs.threshold.network/app-development/tbtc-contracts-api.md) - [Bridge API](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api.md) - [Bank](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/bank.md) - [BitcoinTx](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/bitcointx.md) - [Bridge](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/bridge.md) - [BridgeGovernance](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/bridgegovernance.md) - [BridgeGovernanceParameters](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/bridgegovernanceparameters.md) - [BridgeState](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/bridgestate.md) - [Deposit](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/deposit.md) - [DepositSweep](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/depositsweep.md) - [DonationVault](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/donationvault.md) - [EcdsaLib](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/ecdsalib.md) - [Fraud](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/fraud.md) - [GovernanceUtils](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/governanceutils.md) - [Heartbeat](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/heartbeat.md) - [IReceiveBalanceApproval](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/ireceivebalanceapproval.md) - [IRelay](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/irelay.md) - [IVault](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/ivault.md) - [L2TBTC](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/l2tbtc.md) - [L2WormholeGateway](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/l2wormholegateway.md) - [LightRelay](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/lightrelay.md) - [LightRelayMaintainerProxy](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/lightrelaymaintainerproxy.md) - [MaintainerProxy](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/maintainerproxy.md) - [MovingFunds](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/movingfunds.md) - [Redemption](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/redemption.md) - [TBTC](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/tbtc.md) - [TBTCOptimisticMinting](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/tbtcoptimisticminting.md) - [TBTCVault](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/tbtcvault.md) - [VendingMachine](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/vendingmachine.md) - [VendingMachineV2](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/vendingmachinev2.md) - [VendingMachineV3](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/vendingmachinev3.md) - [WalletCoordinator](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/walletcoordinator.md) - [Wallets](https://docs.threshold.network/app-development/tbtc-contracts-api/tbtc-v2-api/wallets.md) - [ECDSA API](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api.md) - [EcdsaAuthorization](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/ecdsaauthorization.md) - [EcdsaDkg](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/ecdsadkg.md) - [EcdsaDkgValidator](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/ecdsadkgvalidator.md) - [EcdsaInactivity](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/ecdsainactivity.md) - [IWalletOwner](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/iwalletowner.md) - [IWalletRegistry](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/iwalletregistry.md) - [WalletRegistry](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/walletregistry.md) - [WalletRegistryGovernance](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/walletregistrygovernance.md) - [Wallets](https://docs.threshold.network/app-development/tbtc-contracts-api/ecdsa-api/wallets.md) --- # Agent Instructions This documentation is published with GitBook. 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