> ## Documentation Index
> Fetch the complete documentation index at: https://docs.meteora.ag/llms.txt
> Use this file to discover all available pages before exploring further.

# DBC Rust Integration Library

> Learn how to use the DBC Rust library for exact-in, exact-out, partial-fill, account-state inputs, and tests.

The `dynamic-bonding-curve` repository includes a Rust crate at `dynamic-bonding-curve-sdk`. It depends on the on-chain `dynamic-bonding-curve` crate and reuses program state and math types.

## Install

Use the crate from the local workspace or a pinned Git revision:

```toml theme={"system"}
[dependencies]
dynamic-bonding-curve-sdk = { git = "https://github.com/MeteoraAg/dynamic-bonding-curve", package = "dynamic-bonding-curve-sdk" }
```

For local development inside the program repository:

```bash theme={"system"}
cd dynamic-bonding-curve
cargo test -p dynamic-bonding-curve-sdk
```

## What It Provides

| Module               | Function             | Use                                                        |
| -------------------- | -------------------- | ---------------------------------------------------------- |
| `quote_exact_in`     | `quote_exact_in`     | Quote a swap for a fixed input amount.                     |
| `quote_exact_out`    | `quote_exact_out`    | Quote the required input for a fixed output amount.        |
| `quote_partial_fill` | `quote_partial_fill` | Quote a partial-fill swap near the end of a bonding curve. |

The crate is useful for Rust services, quote engines, tests, and keepers that already decode `VirtualPool` and `PoolConfig` accounts.

## Quote Inputs

All three quote helpers require current pool and config state:

| Parameter                                    | Meaning                                                                                                                                 |
| -------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------- |
| `pool: &VirtualPool`                         | Current virtual pool account data.                                                                                                      |
| `config: &PoolConfig`                        | Pool config account referenced by `pool.pool_state.config`.                                                                             |
| `swap_base_for_quote: bool`                  | `true` sells base for quote; `false` buys base with quote.                                                                              |
| `current_timestamp: u64`                     | Current cluster timestamp. Used when `config.activation_type` is timestamp.                                                             |
| `current_slot: u64`                          | Current cluster slot. Used when `config.activation_type` is slot.                                                                       |
| `has_referral: bool`                         | Whether a referral fee should be included. Used by exact-in and partial-fill quotes.                                                    |
| `eligible_for_first_swap_with_min_fee: bool` | Whether the quote should use the first-swap minimum fee path. Set this only when the transaction satisfies the program validation path. |

## Exact-In Quote

```rust theme={"system"}
pub fn quote_exact_in(
    pool: &VirtualPool,
    config: &PoolConfig,
    swap_base_for_quote: bool,
    current_timestamp: u64,
    current_slot: u64,
    in_amount: u64,
    has_referral: bool,
    eligible_for_first_swap_with_min_fee: bool,
) -> anyhow::Result<SwapResult2>
```

Use this for `swap2` exact-in mode, then apply your slippage policy before building the transaction.

## Exact-Out Quote

```rust theme={"system"}
pub fn quote_exact_out(
    pool: &VirtualPool,
    config: &PoolConfig,
    swap_base_for_quote: bool,
    current_timestamp: u64,
    current_slot: u64,
    out_amount: u64,
    eligible_for_first_swap_with_min_fee: bool,
) -> anyhow::Result<SwapResult2>
```

Exact-out quotes return the input amount required to receive `out_amount`. Apply a maximum input bound before sending the transaction.

## Partial-Fill Quote

```rust theme={"system"}
pub fn quote_partial_fill(
    pool: &VirtualPool,
    config: &PoolConfig,
    swap_base_for_quote: bool,
    current_timestamp: u64,
    current_slot: u64,
    in_amount: u64,
    has_referral: bool,
    eligible_for_first_swap_with_min_fee: bool,
) -> anyhow::Result<SwapResult2>
```

Partial fill is useful when the pool is close to `migration_quote_threshold` and a full exact-in swap might cross the migration boundary.

## Return Data

`SwapResult2` contains the values needed by quote engines and transaction builders:

| Field                                         | Use                                             |
| --------------------------------------------- | ----------------------------------------------- |
| `included_fee_input_amount`                   | Input amount before excluded-fee adjustment.    |
| `excluded_fee_input_amount`                   | Amount that moves the curve after fee handling. |
| `amount_left`                                 | Unused amount in partial-fill flows.            |
| `output_amount`                               | Output token amount.                            |
| `next_sqrt_price`                             | Post-swap Q64.64 sqrt price.                    |
| `trading_fee`, `protocol_fee`, `referral_fee` | Fee split for the swap.                         |

## Tests

The Rust crate includes tests for exact-out and partial-fill behavior, plus binary fixtures for configs and pools with quote-token and both-token fee modes.

| Path                                                             | Use                                  |
| ---------------------------------------------------------------- | ------------------------------------ |
| `dynamic-bonding-curve-sdk/src/tests/test_quote_exact_out.rs`    | Exact-out quote tests.               |
| `dynamic-bonding-curve-sdk/src/tests/test_quote_partial_fill.rs` | Partial-fill quote tests.            |
| `dynamic-bonding-curve-sdk/fixtures/*.bin`                       | Serialized pool and config fixtures. |