Adaptor Creation Guide

An adaptor is a Solana program that bridges a Voltr vault with your DeFi protocol. The vault program calls your adaptor via CPI, and your adaptor routes those calls to your protocol.

Building with a coding agent? The Voltr Agent Skill ships an adaptor-creation.md reference and a complete minimal Anchor adaptor in examples/adaptor/ to scaffold this for you.

How It Works

When a vault manager allocates or deallocates funds, the vault program:

Transfers tokens to/from the vault_strategy_auth PDA
Calls your adaptor’s deposit or withdraw instruction via CPI
Reads the returned u64 (via Solana’s get_return_data) to track the strategy’s position value

Your adaptor translates these calls into whatever your protocol needs — initializing markets, minting receipt tokens, managing exchange rates, etc.

Core Requirements

Every adaptor must implement at minimum these three instructions:

Instruction	Called When	Must Return
`initialize`	Strategy is first created	`Result<()>`
`deposit`	Vault allocates funds to strategy	`Result<u64>` — current position value in underlying token terms
`withdraw`	Vault deallocates funds from strategy	`Result<u64>` — remaining position value in underlying token terms

Adaptors can define additional instructions beyond these three for protocol-specific workflows — such as multi-step withdrawals (request → withdraw), reward harvesting, or rebalancing. These extra instructions are invoked by the vault manager via remaining_accounts or separate transactions, not by the vault program itself.

Key Concept: Strategy = Your Protocol’s State

The vault passes a strategy account to your adaptor. This account maps to your protocol’s own state — a market PDA, a reserve, a lending pool, etc. Your adaptor validates this mapping:

// Example: strategy must be the ctoken market account
#[account(constraint = strategy.key() == market.key())]
pub strategy: AccountInfo<'info>,

Each vault strategy is a 1:1 mapping to a specific instance of your protocol.

Accounts Passed by the Vault

The vault program always passes these accounts in a fixed order when calling your adaptor: Initialize: payer, vault_strategy_auth (signer), strategy, system_program, + remaining accounts Deposit / Withdraw: vault_strategy_auth (signer), strategy, vault_asset_mint, vault_strategy_asset_ata, asset_token_program, + remaining accounts Any additional protocol-specific accounts are appended via remaining_accounts.

Overview