Integration Guides

⚠️ API Disclaimer: CBTC APIs are subject to change. Label all examples with the SDK version and DAR version they were tested against.

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Overview

This page provides integration patterns for common CBTC use cases. Each pattern includes architecture notes, key considerations, and pointers to relevant code. For API details, see the API Reference. For authentication setup, see the Authentication Guide.

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Integration Pattern 1: DeFi Protocol

Use case: Build a DEX, lending platform, or liquidity pool using CBTC as collateral.

Architecture

1. Your protocol runs on a Canton participant node with CBTC DAR files installed
2. Users deposit CBTC into your protocol's Canton party via a Transfer choice
3. Your protocol logic (Daml contracts) manages positions, collateral, and settlement
4. Users withdraw CBTC back to their own party when exiting

Key Considerations

• UTXO management: Each transfer creates UTXOs. Keep below 10 per party. Use cbtc-lib consolidation functions.
• Instrument ID: Fetch dynamically - see Instrument ID Management
• Privacy: Canton transactions are private by default. Only parties to a contract see its details. This eliminates MEV.
• Transfer costs: ~$3-5 per CBTC transfer on Canton currently. Factor this into your protocol economics.

Example Partners

• Bron - BTC-CBTC and CC-CBTC swapping on Canton
• Elk Capital Markets / Triangle - OTC and app-based CBTC trading
• Silvana - DEX/trading venue on Canton (coming soon)

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Integration Pattern 2: Wallet or Custody Solution

Use case: Support CBTC in an institutional-grade wallet or custody platform.

Architecture

1. Wallet connects to a Canton participant via the Ledger API
2. Authentication via OIDC (Keycloak supported, Auth0 community example available)
3. CBTC balances queried via state-queries endpoint
4. Transfers executed via Transfer choice on CBTC token contracts

Supported Wallets (Current Ecosystem)

• Loop Wallet - Canton-native wallet with CBTC support
• Console / Zoro Wallet - Canton wallet with API access
• Bron Wallet - Multi-party wallet with testnet support
• WalletConnect - For dApp-to-wallet connections

Key Considerations

• External signing: Available for integration with custody providers (DFNS, Fordefi, Ledger)
• Party creation at scale: If creating 10+ parties, use the Ledger API directly rather than wallet UI - see Canton docs
• CORS: If your wallet makes browser-based API calls, configure CORS on your ingress

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Integration Pattern 3: Trading System

Use case: Build spot trading, perpetual contracts, options, or structured products with CBTC.

Why Canton for Trading

• No public mempool - positions are not visible to other participants, eliminating front-running and sandwich attacks (MEV)
• Private transactions - only parties to a trade see the details
• Audit-ready - Canton's privacy model supports selective disclosure for compliance

Architecture

1. Trading engine runs as Daml contracts on Canton
2. CBTC used as settlement or collateral asset
3. Counterparty discovery and matching handled by your protocol
4. Settlement is atomic - either both sides complete or neither does

Example: Options on CBTC

CBTC holders can write covered CALL options, earning premium income while maintaining BTC exposure. Settlement uses Canton's atomic dual-token transfer - the buyer receives the underlying asset while the seller receives payment, atomically.

DvP Settlement Using Allocations

For atomic delivery-versus-payment, cbtc-lib provides the cbtc::allocation module, which implements the Canton Token Standard allocation lifecycle. This is the mechanism behind the atomic settlement described above.

How it differs from a standard transfer. The two-phase transfer / accept flow described in the Quick Start is free-of-payment (FOP): the sender offers CBTC, the receiver accepts, and nothing is exchanged in return. There is no linkage to a second leg. An allocation instead locks CBTC into one leg of a multi-leg settlement that a third party settles atomically, so the CBTC only moves if the other leg moves too.

	FOP transfer (cbtc::transfer + cbtc::accept)	DvP allocation (cbtc::allocation)
Parties	Sender, receiver	Sender, receiver, settlement executor (the venue)
Settled by	The receiver, by accepting	The executor, across all legs at once
Atomicity	Single leg only	All legs settle together or none do
Sender can reclaim	Cancel the offer (cbtc::cancel_offers)	Withdraw the allocation before settlement
Deadlines	execute_before	allocate_before, then settle_before

Lifecycle. The sender locks their leg, then the executor settles:

1. Allocate - the leg sender calls cbtc::allocation::allocate, which exercises AllocationFactory_Allocate and locks the sender's holdings. If no input holdings are specified, the library auto-selects them.
2. Execute - the settlement executor calls cbtc::allocation::execute_transfer (Allocation_ExecuteTransfer). A coordinating app normally settles every leg together in a single transaction; the library exposes the single-leg choice for that purpose.
3. Or unwind - the sender can call cbtc::allocation::withdraw (Allocation_Withdraw) to reclaim locked holdings before settlement, and cbtc::allocation::cancel (Allocation_Cancel) releases them back to the sender.

Timing. An allocation must be funded before allocate_before and settled before settle_before, which must be the later of the two.

Allocating CBTC into a settlement leg:

use cbtc::allocation;

let allocation_spec = common::allocation::AllocationSpecification {
 settlement: common::allocation::SettlementInfo {
 executor: executor_party_id.clone(), // the venue settling the legs
 settlement_ref: common::allocation::Reference {
 id: settlement_ref_id.clone(),
 cid: None,
 },
 requested_at: now.to_rfc3339(),
 allocate_before: (now + chrono::Duration::hours(24)).to_rfc3339(),
 settle_before: (now + chrono::Duration::hours(48)).to_rfc3339(),
 meta: common::allocation::Metadata::default(),
 },
 transfer_leg_id: "leg0".to_string(),
 transfer_leg: common::allocation::TransferLeg {
 sender: sender_party_id.clone(),
 receiver: receiver_party_id.clone(),
 amount: cbtc::DamlDecimal::parse("0.1")?,
 instrument_id: common::transfer::InstrumentId {
 admin: decentralized_party_id.clone(),
 id: "CBTC".to_string(),
 },
 meta: common::allocation::Metadata::default(),
 },
};

allocation::allocate(allocation::Params {
 allocation: allocation_spec,
 requested_at: now.to_rfc3339(),
 input_holding_cids: Vec::new(), // empty = library auto-selects the sender's holdings
 ledger_host: ledger_host.clone(),
 access_token: access_token.clone(),
 registry_url: registry_url.clone(),
 decentralized_party_id: decentralized_party_id.clone(),
}).await?;

Reclaiming an allocation before settlement:

use cbtc::allocation;

allocation::withdraw(allocation::ActionParams {
 allocation_contract_id: allocation_cid.clone(),
 actor_party: sender_party_id.clone(),
 ledger_host: ledger_host.clone(),
 access_token: access_token.clone(),
 registry_url: registry_url.clone(),
 decentralized_party_id: decentralized_party_id.clone(),
}).await?;

💡 No Minter credential needed. Allocations move existing CBTC rather than creating or destroying it, so they do not require the Minter credential that minting and burning do.

A complete runnable example is in the library: examples/allocate_cbtc.rs. For the underlying standard, see the Canton Token Standard allocation docs.

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Integration Pattern 4: Minting Integration

Use case: Offer CBTC minting as a service to your users.

Three Options

Option	Description	Effort
1. Direct API	Install CBTC DAR, call Canton APIs to mint/redeem	Low - a few hours
2. Self-hosted UI	Install DAR + BitSafe minting UI locally	Medium - more maintenance
3. Hosted UI (coming soon)	Use BitSafe's centrally hosted UI against your validator.	TBD

For Option 1, see the Minting and Burning Guide and API Reference.

For Options 2 and 3, contact BitSafe for setup details.

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Getting Started

1. Install the SDK and DAR files - see SDK Setup and Installation for cbtc-lib, canton-lib, DAR upload, and environment configuration
2. Set up testnet first - see Testnet Guide
3. Mint your first CBTC - see Quick Start
4. Review examples - GitHub examples Need help? Reach out via [e-mail]

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