> ## 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.

# Stake2Earn Rust Integration Library

> Understand the Stake2Earn Rust integration surface, including the generated stake_for_fee_interface crate, common PDA helpers, account decoders, instruction builders, events, and errors.

The local Rust integration source contains two crates:

| Crate                     | Path                                        | Use                                                                                |
| ------------------------- | ------------------------------------------- | ---------------------------------------------------------------------------------- |
| `stake_for_fee_interface` | `stake-for-fee-sdk/stake_for_fee_interface` | Generated Rust interface for accounts, instructions, typedefs, events, and errors. |
| `common`                  | `stake-for-fee-sdk/common`                  | Small PDA helper crate that depends on `stake_for_fee_interface` as `m3m3`.        |

<Note>
  The inspected source does not include a high-level ergonomic Rust SDK like the TypeScript `StakeForFee` class. Rust integrations should use the generated interface crate, PDA helpers, and fresh on-chain account reads.
</Note>

## Workspace

```toml theme={"system"}
[workspace]
members = ["stake_for_fee_interface", "common"]
resolver = "2"
```

For local development against the source checkout:

```toml theme={"system"}
[dependencies]
stake_for_fee_interface = { path = "../stake-for-fee-sdk/stake_for_fee_interface" }
common = { path = "../stake-for-fee-sdk/common" }
```

## Program ID

`stake_for_fee_interface` declares the public program ID:

| Program         | ID                                             |
| --------------- | ---------------------------------------------- |
| `stake_for_fee` | `FEESngU3neckdwib9X3KWqdL7Mjmqk9XNp3uh5JbP4KP` |

## PDA Helpers

The `common::pda` module exports:

| Function                                  | Derives                                                |
| ----------------------------------------- | ------------------------------------------------------ |
| `derive_m3m3_vault_key(pool_key)`         | `["vault", pool]` under `stake_for_fee_interface::ID`. |
| `derive_top_staker_list_key(vault_key)`   | `["list", vault]`.                                     |
| `derive_full_balance_list_key(vault_key)` | `["balance", vault]`.                                  |
| `derive_m3m3_event_authority_key()`       | Anchor Event CPI authority `["__event_authority"]`.    |

```rust theme={"system"}
use common::pda::{
    derive_full_balance_list_key, derive_m3m3_event_authority_key,
    derive_m3m3_vault_key, derive_top_staker_list_key,
};
use solana_sdk::pubkey::Pubkey;

let pool = Pubkey::new_unique();
let vault = derive_m3m3_vault_key(pool);
let top_list = derive_top_staker_list_key(vault);
let full_balance_list = derive_full_balance_list_key(vault);
let event_authority = derive_m3m3_event_authority_key();
```

## Generated Modules

| Module         | Exports                                                                                                                                                                  |
| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `accounts`     | Account structs, discriminators, and `deserialize` helpers for `FeeVault`, `StakeEscrow`, `Unstake`, list metadata, and dummy account wrappers used for generated types. |
| `typedefs`     | `InitializeVaultParams`, `StakerBalance`, `StakerMetadata`, `Configuration`, `Metrics`, `TopStakerInfo`, and `Rounding`.                                                 |
| `instructions` | Instruction enum, discriminators, key structs, argument structs, `*_ix`, `*_invoke`, and `*_invoke_signed` helpers.                                                      |
| `events`       | Event structs matching the Anchor event definitions.                                                                                                                     |
| `errors`       | `StakeForFeeError` enum with custom codes `6000` through `6022`.                                                                                                         |

## Instruction Builders

| Helper                                         | Args                                                         | Use                                                     |
| ---------------------------------------------- | ------------------------------------------------------------ | ------------------------------------------------------- |
| `initialize_vault_ix(keys, args)`              | `InitializeVaultIxArgs { params }`                           | Create the root vault and list accounts.                |
| `initialize_stake_escrow_ix(keys)`             | None                                                         | Create a user stake escrow.                             |
| `stake_ix(keys, args)`                         | `StakeIxArgs { amount }`                                     | Stake tokens and sync lists.                            |
| `claim_fee_ix(keys, args)`                     | `ClaimFeeIxArgs { max_fee }`                                 | Claim quote fees and restake base fees.                 |
| `request_unstake_ix(keys, args)`               | `RequestUnstakeIxArgs { unstake_amount }`                    | Create a pending unstake request.                       |
| `cancel_unstake_ix(keys)`                      | None                                                         | Cancel an open unstake request.                         |
| `withdraw_ix(keys)`                            | None                                                         | Withdraw released stake.                                |
| `claim_fee_crank_ix(keys)`                     | None                                                         | Permissionlessly claim and distribute lock escrow fees. |
| `update_unstake_lock_duration_ix(keys, args)`  | `UpdateUnstakeLockDurationIxArgs { unstake_lock_duration }`  | Admin update for future unstake cooldowns.              |
| `update_seconds_to_full_unlock_ix(keys, args)` | `UpdateSecondsToFullUnlockIxArgs { seconds_to_full_unlock }` | Admin update for fee drip duration after a crank.       |

Each instruction also has `*_ix_with_program_id`, `*_invoke`, `*_invoke_with_program_id`, `*_invoke_signed`, and verification helpers in the generated source.

## Account Decoding

| Account wrapper                                     | Use                                       |
| --------------------------------------------------- | ----------------------------------------- |
| `FeeVaultAccount::deserialize(data)`                | Decode root vault state.                  |
| `StakeEscrowAccount::deserialize(data)`             | Decode a user stake escrow.               |
| `UnstakeAccount::deserialize(data)`                 | Decode a pending unstake account.         |
| `TopListMetadataAccount::deserialize(data)`         | Decode only the top-list header.          |
| `FullBalanceListMetadataAccount::deserialize(data)` | Decode only the full-balance-list header. |

Top and full balance list entries are appended after the account discriminator and metadata header. Use the TypeScript decoder logic as a model if you need to parse appended entries in Rust.

## Error Decoding

`StakeForFeeError` implements `From<StakeForFeeError> for ProgramError`, `DecodeError`, and `PrintProgramError`.

| Code range       | Meaning                                        |
| ---------------- | ---------------------------------------------- |
| `6000` to `6022` | Stake2Earn custom errors from `stake_for_fee`. |

See the [program error reference](/developer-guides/stake2earn/program/errors) for the full table.