Stake Pool Program

A program for pooling together SOL to be staked by an off-chain agent running a Delegation Bot which redistributes the stakes across the network and tries to maximize censorship resistance and rewards.

Overview

SOL token holders can earn rewards and help secure the network by staking tokens to one or more validators. Rewards for staked tokens are based on the current inflation rate, total number of SOL staked on the network, and an individual validator’s uptime and commission (fee).

Stake pools are an alternative method of earning staking rewards. This on-chain program pools together SOL to be staked by a staker, allowing SOL holders to stake and earn rewards without managing stakes.

Additional information regarding staking and stake programming is available at:

Quick Start

If you're looking to get immediately into creating and running a stake pool, take a look at the reference scripts.

These scripts require the Solana CLI tool suite, which can be downloaded by following the instructions at (https://docs.solana.com/cli/install-solana-cli-tools). Additionally, you must have a usable keypair, created at the default location using solana-keygen new.

You'll see the following scripts:

setup-local.sh: sets up a local test validator with validator vote accounts
setup-stake-pool.sh: creates a new stake pool with hardcoded parameters
deposit-withdraw.sh: performs some deposits and withdrawals

The CLI README contains more information about each of these scripts.

Motivation

This document is intended for the main actors of the stake pool system:

manager: creates and manages the stake pool, earns fees, can update the fee, staker, and manager
staker: adds and removes validators to the pool, rebalances stake among validators
user: provides staked SOL into an existing stake pool

In its current iteration, the stake pool accepts active stakes or SOL, so deposits may come from either an active stake or SOL wallet. Withdrawals can return a fully active stake account from one of the stake pool's accounts, or SOL from the reserve.

This means that stake pool managers and stakers must be comfortable with creating and delegating stakes, which are more advanced operations than sending and receiving SPL tokens and SOL. Additional information on stake operations are available at:

To reach a wider audience of users, stake pool managers are encouraged to provide a market for their pool's tokens, through an AMM like Token Swap.

Alternatively, stake pool managers can partner with wallet and stake account providers for direct SOL deposits.

Operation

A stake pool manager creates a stake pool, and the staker includes validators that will receive delegations from the pool by adding "validator stake accounts" to the pool using the add-validator instruction. In this command, the stake pool creates a new stake account and delegates it to the desired validator.

At this point, users can participate with deposits. They can directly deposit SOL into the stake pool using the deposit-sol instruction. Within this instruction, the stake pool will move SOL into the pool's reserve account, to be redistributed by the staker.

Alternatively, users can deposit a stake account into the pool. To do this, they must delegate a stake account to the one of the validators in the stake pool. If the stake pool has a preferred deposit validator, the user must delegate their stake to that validator's vote account.

Once the stake becomes active, which happens at the following epoch boundary (maximum 2 days), the user can deposit their stake into the pool using the deposit-stake instruction.

In exchange for their deposit (SOL or stake), the user receives SPL tokens representing their fractional ownership in pool. A percentage of the rewards earned by the pool goes to the pool manager as an epoch fee.

Over time, as the stakes in the pool accrue rewards, the user's fractional ownership will be worth more than their initial deposit.

Whenever they wish to exit the pool, the user may use the withdraw-sol instruction to receive SOL from the stake pool's reserve in exchange for stake pool tokens. Note that this operation will fail if there is not enough SOL in the stake pool's reserve, which is normal if the stake pool manager stakes all of the SOL in the pool.

Alternatively, they can use the withdraw-stake instruction to withdraw an activated stake account in exchange for their SPL pool tokens. The user will get back a SOL stake account immediately. The ability to withdraw stake is always possible, under all circumstances.

Note: when withdrawing stake, if the user wants to withdraw the SOL in the stake account, they must first deactivate the stake account and wait until the next epoch boundary (maximum 2 days). Once the stake is inactive, they can freely withdraw the SOL.

The stake pool staker can add and remove validators, or rebalance the pool by decreasing the stake on a validator, waiting an epoch to move it into the stake pool's reserve account, then increasing the stake on another validator.

The staker operation to add a new validator requires 0.00328288 SOL to create the stake account on a validator, so the stake pool staker will need liquidity on hand to fully manage the pool stakes. The SOL used to add a new validator is recovered when removing the validator.

Fees

The stake pool program provides managers many options for making the pool financially viable, predominantly through fees. There are five different sources of fees:

Epoch: every epoch (roughly 2 days), the stake accounts in the pool earn inflation rewards, so the stake pool mints pool tokens into the manager's fee account as a proportion of the earned rewards. For example, if the pool earns 10 SOL in rewards, and the fee is set to 2%, the manager will earn pool tokens worth 0.2 SOL.
SOL withdraw: sends a proportion of the desired withdrawal amount to the manager For example, if a user wishes to withdraw 100 pool tokens, and the fee is set to 3%, 3 pool tokens go to the manager, and the remaining 97 tokens go to the user in the form of a SOL.
Stake withdraw: sends a proportion of the desired withdrawal amount to the manager before creating a new stake for the user.
SOL deposit: converts the entire SOL deposit into pool tokens, then sends a proportion of those to the manager, and the rest to the user
Stake deposit: converts the stake account's delegation plus rent-exemption to pool tokens, sends a proportion of those to the manager, and the rest to the user

For partner applications, there's the option of a referral fee on deposits. During SOL or stake deposits, the stake pool can redistribute a percentage of the fees to another address as a referral fee.

This option is particularly attractive for wallet providers. When a wallet integrates a stake pool, the wallet developer will have the option to earn additional tokens anytime a user deposits into the stake pool. Stake pool managers can use this feature to create strategic partnerships and entice greater adoption of stake pools!

Funding restrictions

To give the manager more control over funds entering the pool, stake pools allow deposit and withdrawal restrictions on SOL and stakes through three different "funding authorities":

SOL deposit
Stake deposit
SOL withdrawal

If the field is set, that authority must sign the associated instruction.

For example, if the manager sets a stake deposit authority, then that address must sign every stake deposit instruction.

This can also be useful in a few situations:

Control who deposits into the stake pool
Prohibit a form of deposit. For example, the manager only wishes to have SOL deposits, so they set a stake deposit authority, making it only possible to deposit a stake account if that authority signs the transaction.
Maintenance mode. If the pool needs time to reset fees or otherwise, the manager can temporarily restrict new deposits by setting deposit authorities.

Note: in order to keep user funds safe, stake withdrawals are always permitted.

Background

Solana's programming model and the definitions of the Solana terms used in this document are available at:

Source

The Stake Pool Program's source is available on GitHub.

For information about the types and instructions, the Stake Pool Rust docs are available at docs.rs.

Security Audits

Multiple security firms have audited the stake pool program to ensure total safety of funds. The audit reports are available for reading, presented in descending chronological order, and the commit hash that each was reviewed at:

Quantstamp
- Initial review commit hash 99914c9
- Re-review commit hash 3b48fa0
- Final report https://solana.com/SolanaQuantstampStakePoolAudit.pdf
Neodyme
- Review commit hash 0a85a9a
- Report https://solana.com/SolanaNeodymeStakePoolAudit.pdf
Kudelski
- Review commit hash 3dd6767
- Report https://solana.com/SolanaKudelskiStakePoolAudit.pdf

Command-line Utility

The following explains the instructions available in the Stake Pool Program along with examples using the command-line utility.

The spl-stake-pool command-line utility can be used to experiment with SPL tokens. Once you have Rust installed, run:

$ cargo install spl-stake-pool-cli

Run spl-stake-pool --help for a full description of available commands.

Configuration

The spl-stake-pool configuration is shared with the solana command-line tool.

Current Configuration

solana config get
Config File: ${HOME}/.config/solana/cli/config.yml
RPC URL: https://api.mainnet-beta.solana.com
WebSocket URL: wss://api.mainnet-beta.solana.com/ (computed)
Keypair Path: ${HOME}/.config/solana/id.json

Cluster RPC URL

See Solana clusters for cluster-specific RPC URLs

solana config set --url https://api.devnet.solana.com

Default Keypair

See Keypair conventions for information on how to setup a keypair if you don't already have one.

Keypair File

solana config set --keypair ${HOME}/new-keypair.json

Hardware Wallet URL (See URL spec)

solana config set --keypair usb://ledger/

Run Locally

If you would like to test a stake pool locally without having to wait for stakes to activate and deactivate, you can run the stake pool locally using the solana-test-validator tool with shorter epochs, and pulling the current program from devnet.

$ solana-test-validator -c SPoo1Ku8WFXoNDMHPsrGSTSG1Y47rzgn41SLUNakuHy -c EmiU8AQkB2sswTxVB6aCmsAJftoowZGGDXuytm6X65R3 --url devnet --slots-per-epoch 32
$ solana config set --url http://127.0.0.1:8899

Stake Pool Manager Examples

Create a stake pool

The stake pool manager controls the stake pool from a high level, and in exchange receives a fee in the form of SPL tokens. The manager sets the fee on creation. Let's create a pool with a 3% fee and a maximum of 1000 validator stake accounts:

$ spl-stake-pool create-pool --epoch-fee-numerator 3 --epoch-fee-denominator 100 --max-validators 1000
Creating reserve stake DVwDn4LTRztuai4QeenM6fyzgiwUGpVXVNZ1mgKE1Pyc
Creating mint BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Creating associated token account DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ to receive stake pool tokens of mint BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB, owned by 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Creating pool fee collection account DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ
Signature: qQwqahLuC24wPwVdgVXtd7v5htSSPDAH3JxFNmXCv9aDwjjqygQ64VMg3WdPCiNzc4Bn8vtS3qcnUVHVP5MbKgL
Creating stake pool Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Signature: 5z6uH3EuPcujeWGpAjBtciSUR3TxtMBgWYU4ULagUso4QGzE9JenhYHwYthJ4b3rS57ByUNEXTr2BFyF5PjWC42Y

The unique stake pool identifier is Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR.

The identifier for the stake pool's SPL token mint is BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB. The stake pool has full control over the mint.

The pool creator's fee account identifier is DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ. Every epoch, as stake accounts in the stake pool earn rewards, the program will mint SPL pool tokens equal to 3% of the gains on that epoch into this account. If no gains were observed, nothing will be deposited.

The reserve stake account identifier is J5XB7mWpeaUZxZ6ogXT57qSCobczx27vLZYSgfSbZoBB. This account holds onto additional stake used when rebalancing between validators.

For a stake pool with 1000 validators, the cost to create a stake pool is less than 0.5 SOL.

The create-pool command allows setting all of the accounts and keypairs to pre-generated values, including:

stake pool, through the --pool-keypair flag
validator list, through the --validator-list-keypair flag
pool token mint, through the --mint-keypair flag
pool reserve stake account, through the --reserve-keypair flag

Otherwise, these will all default to newly-generated keypairs.

You can always check out the available options by running spl-stake-pool create-pool -h.

Create a restricted stake pool

If a manager would like to restrict deposits (stake and SOL) to one key in particular, they can set a deposit authority at creation:

$ spl-stake-pool create-pool --epoch-fee-numerator 3 --epoch-fee-denominator 100 --max-validators 1000 --deposit-authority authority_keypair.json
Creating reserve stake DVwDn4LTRztuai4QeenM6fyzgiwUGpVXVNZ1mgKE1Pyc
Creating mint BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Creating associated token account DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ to receive stake pool tokens of mint BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB, owned by 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Creating pool fee collection account DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ
Signature: qQwqahLuC24wPwVdgVXtd7v5htSSPDAH3JxFNmXCv9aDwjjqygQ64VMg3WdPCiNzc4Bn8vtS3qcnUVHVP5MbKgL
Creating stake pool Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Deposits will be restricted to 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn only, this can be changed using the set-funding-authority command.
Signature: 5z6uH3EuPcujeWGpAjBtciSUR3TxtMBgWYU4ULagUso4QGzE9JenhYHwYthJ4b3rS57ByUNEXTr2BFyF5PjWC42Y

As the output says, the set-funding-authority can be used to modify or remove the deposit authority.

As long as the deposit authority is set, SOL and stake deposits must be signed by 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn, so no one else can participate in the pool. As mentioned earlier, this feature does not prohibit withdrawals, so anyone with pool tokens will still be able to withdraw from the pool.

Set manager

The stake pool manager may pass their administrator privileges to another account.

$ spl-stake-pool set-manager Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR --new-manager 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Signature: 39N5gkaqXuWm6JPEUWfenKXeG4nSa71p7iHb9zurvdZcsWmbjdmSXwLVYfhAVHWucTY77sJ8SkUNpVpVAhe4eZ53

At the same time, they may also change the SPL token account that receives fees every epoch. The mint for the provided token account must be the SPL token mint, BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB in our example.

$ spl-stake-pool set-manager Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR --new-fee-receiver HoCsh97wRxRXVjtG7dyfsXSwH9VxdDzC7GvAsBE1eqJz
Signature: 4aK8yzYvPBkP4PyuXTcCm529kjEH6tTt4ixc5D5ZyCrHwc4pvxAHj6wcr4cpAE1e3LddE87J1GLD466aiifcXoAY

Set fee

The stake pool manager may update any of the fees associated with the stake pool, passing the numerator and denominator for the fraction that make up the fee.

For an epoch fee of 10%, they could run:

$ spl-stake-pool set-fee Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR epoch 10 100
Signature: 5yPXfVj5cbKBfZiEVi2UR5bXzVDuc2c3ruBwSjkAqpvxPHigwGHiS1mXQVE4qwok5moMWT5RNYAMvkE9bnfQ1i93

In order to protect stake pool depositors from malicious managers, the program applies the new fee for the following epoch.

For example, if the fee is 1% at epoch 100, and the manager sets it to 10%, the manager will still gain 1% for the rewards earned during epoch 100. Starting with epoch 101, the manager will earn 10%.

Additionally, to prevent a malicious manager from immediately setting the withdrawal fee to a very high amount, making it practically impossible for users to withdraw, the stake pool program currently enforces a limit of 1.5x increase per epoch.

For example, if the current withdrawal fee is 2.5%, the maximum that can be set for the next epoch is 3.75%.

The possible options for the fee type are epoch, sol-withdrawal, stake-withdrawal, sol-deposit, and stake-deposit.

Set referral fee

The stake pool manager may update the referral fee on deposits at any time, passing in a percentage amount.

To set a stake deposit referral fee of 80%, they may run:

$ spl-stake-pool set-referral-fee Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR stake 80
Signature: 4vhaBEDhuKkVwMxy7TpyfHEk3Z5kGZKerD1AgajQBdiMRQLZuNZKVR3KQaqbUYZM7UyfRXgkZNdAeP1NfvmwKdqb

For 80%, this means that 20% of the stake deposit fee goes to the manager, and 80% goes to the referrer.

Set staker

In order to manage the stake accounts, the stake pool manager or staker can set the staker authority of the stake pool's managed accounts.

$ spl-stake-pool set-staker Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Signature: 39N5gkaqXuWm6JPEUWfenKXeG4nSa71p7iHb9zurvdZcsWmbjdmSXwLVYfhAVHWucTY77sJ8SkUNpVpVAhe4eZ53

Now, the new staker can perform any normal stake pool operations, including adding and removing validators and rebalancing stake.

Important security note: the stake pool program only gives staking authority to the pool staker and always retains withdraw authority. Therefore, a malicious stake pool staker cannot steal funds from the stake pool.

Note: to avoid "disturbing the manager", the staker can also reassign their stake authority.

Set Funding Authority

To restrict who can interact with the pool, the stake pool manager may require a particular signature on stake deposits, SOL deposits, or SOL withdrawals. This does not make the pool private, since all information is available on-chain, but it restricts who can use the pool.

As an example, let's say a pool wants to restrict all SOL withdrawals.

$ spl-stake-pool set-funding-authority Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR sol-withdraw AZ1PgxWSxw4ezX8gvpNgGsr39jJHCwtkaXr1mNMwWWeK
Signature: 3gx7ckGNSL7gUUyxh4CU3RH3Lyt88hiCvYQ4QRKtnmrZHvAS93ebP6bf39WYGTeKDMVSJUuwBEmk9VFSaWtXsHVV

After running this command, AZ1PgxWSxw4ezX8gvpNgGsr39jJHCwtkaXr1mNMwWWeK must sign all SOL withdrawals, otherwise the operation fails.

After some time, if the manager wishes to enable SOL withdrawals, they can remove the restriction:

$ spl-stake-pool set-funding-authority Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR sol-withdraw --unset
Signature: 5kWeBqoxyvANMHCP4ydsZRf8QU4hMotLnKkFbTEdvqEVywo4F3MpZtay7D57FbjJZpdp72fc3vrbxJi9qDLfLCnD

Now, anyone can withdraw SOL from the stake pool, provided there is enough SOL left in the reserve.

The options for funding authorities are sol-withdraw, sol-deposit, and stake-deposit.

Note: it is impossible to restrict stake withdrawals. This would create an opportunity for malicious pool managers to effectively lock user funds.

Stake Pool Staker Examples

Add a validator to the pool

In order to accommodate large numbers of user deposits into the stake pool, the stake pool only manages one stake account per validator. To add a new validator to the stake pool, the staker must use the add-validator command.

Let's add some random validators to the stake pool.

$ spl-stake-pool add-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk
Adding stake account F8e8Ympp4MkDSPZdvRxdQUZXRkMBDdyqgHa363GShAPt, delegated to 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk
Signature: 5tdpsx64mVcSHBK8vMbBzFDHnEZB6GUmVpqSXXE5hezMAzPYwZbJCBtAHakDAiuWNcrMongGrmwDaeywhVz4i8pi

In order to maximize censorship resistance, we want to distribute our SOL to as many validators as possible, so let's add a few more.

$ spl-stake-pool add-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H
Adding stake account 5AaobwjccyHnXhFCd24uiX6VqPjXE3Ry4o92fJjqqjAr, delegated to J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H
Signature: 4xeve6gWuiffqBLAMcqa8s7dCMvBmSVdKbDu5WQhigLiXHdCjSNEwoZRexTZji786qgEjXg3nrUh4HcTt3RauZV5
$ spl-stake-pool add-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Adding stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Signature: 4VJYHpPmWkP99TdgYUTgLYixmhqmqsEkWtg4j7zvGZFjYbnLgryu48aV6ub8bqDyULzKckUhb6tvcmZmMX5AFf5G

We can see the status of a stake account using the Solana command-line utility.

$ solana stake-account 5AaobwjccyHnXhFCd24uiX6VqPjXE3Ry4o92fJjqqjAr
Balance: 0.00328288 SOL
Rent Exempt Reserve: 0.00228288 SOL
Delegated Stake: 0.001 SOL
Active Stake: 0 SOL
Activating Stake: 0.001 SOL
Stake activates starting from epoch: 5
Delegated Vote Account Address: J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H
Stake Authority: DS3AyFN9dF1ruNBcSeo8XXQR8UyVMhcCPcnjU5GnY18S
Withdraw Authority: DS3AyFN9dF1ruNBcSeo8XXQR8UyVMhcCPcnjU5GnY18S

The stake pool creates these special staking accounts with 0.001 SOL as the required minimum delegation amount. The stake and withdraw authorities are the stake pool withdraw authority, program addresses derived from the stake pool's address.

We can also see the status of the stake pool.

$ spl-stake-pool list Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Stake Pool: Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Pool Token Mint: BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Epoch Fee: 3/100 of epoch rewards
Withdrawal Fee: none
Stake Deposit Fee: none
SOL Deposit Fee: none
SOL Deposit Referral Fee: none
Stake Deposit Referral Fee: none
Reserve Account: EN4px2h4gFkYtsQUi4yeCYBrdRM4DoRxCVJyavMXEAm5   Available Balance: ◎0.000000000
Vote Account: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ      Balance: ◎0.000000000 Last Update Epoch: 4
Vote Account: J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H      Balance: ◎0.000000000  Last Update Epoch: 4
Vote Account: 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk      Balance: ◎0.000000000  Last Update Epoch: 4
Total Pool Stake: ◎0.000000000
Total Pool Tokens: 0.00000000
Current Number of Validators: 3
Max Number of Validators: 1000

To make reading easier, the tool will not show balances that cannot be touched by the stake pool. The stake account 5AaobwjccyHnXhFCd24uiX6VqPjXE3Ry4o92fJjqqjAr, delegated to J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H, actually has a balance of 0.00328288 SOL, but since this is the minimum required amount, it is not shown by the CLI.

Remove validator stake account

If the stake pool staker wants to stop delegating to a vote account, they can totally remove the validator stake account from the stake pool.

As with adding a validator, the validator stake account must have exactly 0.00328288 SOL (0.001 SOL delegated, 0.00228288 SOL for rent exemption) to be removed.

If that is not the case, the staker must first decrease the stake to that minimum amount. Let's assume that the validator stake account delegated to J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H has a total delegated amount of 7.5 SOL. To reduce that number, the staker can run:

$ spl-stake-pool decrease-validator-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H 6.5
Signature: ZpQGwT85rJ8Y9afdkXhKo3TVv4xgTz741mmZj2vW7mihYseAkFsazWxza2y8eNGY4HDJm15c1cStwyiQzaM3RpH

Now, let's try to remove validator J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H, with stake account 5AaobwjccyHnXhFCd24uiX6VqPjXE3Ry4o92fJjqqjAr.

$ spl-stake-pool remove-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H
Removing stake account 5AaobwjccyHnXhFCd24uiX6VqPjXE3Ry4o92fJjqqjAr, delegated to J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H
Creating account to receive stake nHEEyey8KkgHuVRAUDzkH5Q4PkA4veSHuTxgG6C8L2G
Signature: 4XprnR768Ch6LUvqUVLTjMCiqdYvtjNfECh4izErqwbsASTGjUBz7NtLZHAiraTqhs7b9PoSAazetdsgXa6J4wVu

Unlike a normal withdrawal, the validator stake account is totally moved from the stake pool and into a new account belonging to the administrator.

Note: since removal is only possible when the validator stake is at the minimum amount of 0.00328288, the administrator does not get any control of user funds, and only recovers the amount contributed during add-validator.

The authority for the withdrawn stake account can also be specified using the --new-authority flag:

$ spl-stake-pool remove-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H --new-authority 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Signature: 5rrQ3xhDWyiPkUTAQkNAeq31n6sMf1xsg2x9hVY8Vj1NonwBnhxuTv87nADLkwC8Xzc4CGTNCTX2Vph9esWnXk2d

We can check the removed stake account:

$ solana stake-account nHEEyey8KkgHuVRAUDzkH5Q4PkA4veSHuTxgG6C8L2G
Balance: 0.003282880 SOL
Rent Exempt Reserve: 0.00328288 SOL
Delegated Stake: 0.001000000 SOL
Active Stake: 0.001000000 SOL
Delegated Vote Account Address: J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H
Stake Authority: 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Withdraw Authority: 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn

Rebalance the stake pool

As time goes on, users will deposit to and withdraw from all of the stake accounts managed by the pool, and the stake pool staker may want to rebalance the stakes.

For example, let's say the staker wants the same delegation to every validator in the pool. When they look at the state of the pool, they see:

$ spl-stake-pool list Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Stake Pool: Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Pool Token Mint: BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Epoch Fee: 3/100 of epoch rewards
Withdrawal Fee: none
Stake Deposit Fee: none
SOL Deposit Fee: none
SOL Deposit Referral Fee: none
Stake Deposit Referral Fee: none
Reserve Account: EN4px2h4gFkYtsQUi4yeCYBrdRM4DoRxCVJyavMXEAm5   Available Balance: ◎10.006848640
Vote Account: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ      Balance: ◎100.000000000 Last Update Epoch: 4
Vote Account: J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H      Balance: ◎10.000000000  Last Update Epoch: 4
Vote Account: 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk      Balance: ◎10.000000000  Last Update Epoch: 4
Total Pool Stake: ◎130.006848640
Total Pool Tokens: 130.00684864
Current Number of Validators: 3
Max Number of Validators: 1000

This isn't great! The first stake account, EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ has too much allocated. For their strategy, the staker wants the 100 SOL to be distributed evenly, meaning 40 in each account. They need to move 30 to J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H and 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk.

Decrease validator stake

First, they need to decrease the amount on stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ, by a total of 60 SOL.

They decrease that amount of SOL:

$ spl-stake-pool decrease-validator-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ 60
Signature: ZpQGwT85rJ8Y9afdkXhKo3TVv4xgTz741mmZj2vW7mihYseAkFsazWxza2y8eNGY4HDJm15c1cStwyiQzaM3RpH

Internally, this instruction splits and deactivates 60 SOL from the validator stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx into a transient stake account, owned and managed entirely by the stake pool.

Once the stake is deactivated during the next epoch, the update command will automatically merge the transient stake account into a reserve stake account, also entirely owned and managed by the stake pool.

Increase validator stake

Now that the reserve stake account has enough to perform the rebalance, the staker can increase the stake on the two other validators, J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H and 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk.

They add 30 SOL to J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H:

$ spl-stake-pool increase-validator-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H 30
Signature: 3GJACzjUGLPjcd9RLUW86AfBLWKapZRkxnEMc2yHT6erYtcKBgCapzyrVH6VN8Utxj7e2mtvzcigwLm6ZafXyTMw

And they add 30 SOL to 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk:

$ spl-stake-pool increase-validator-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk 30
Signature: 4zaKYu3MQ3as8reLbuHKaXN8FNaHvpHuiZtsJeARo67UKMo6wUUoWE88Fy8N4EYQYicuwULTNffcUD3a9jY88PoU

Internally, this instruction also uses transient stake accounts. This time, the stake pool splits from the reserve stake, into the transient stake account, then activates it to the appropriate validator.

One to two epochs later, once the transient stakes activate, the update command automatically merges the transient stakes into the validator stake account, leaving a fully rebalanced stake pool:

$ spl-stake-pool list Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Stake Pool: Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Pool Token Mint: BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Preferred Deposit Validator: 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk
Epoch Fee: 3/100 of epoch rewards
Withdrawal Fee: none
Stake Deposit Fee: none
SOL Deposit Fee: none
SOL Deposit Referral Fee: none
Stake Deposit Referral Fee: none
Reserve Account: EN4px2h4gFkYtsQUi4yeCYBrdRM4DoRxCVJyavMXEAm5   Available Balance: ◎10.006848640
Vote Account: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ      Balance: ◎40.000000000  Last Update Epoch: 8
Vote Account: J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H      Balance: ◎40.000000000  Last Update Epoch: 8
Vote Account: 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk      Balance: ◎40.000000000  Last Update Epoch: 8
Total Pool Stake: ◎130.006848640
Total Pool Tokens: 130.00684864
Current Number of Validators: 3
Max Number of Validators: 1000

Due to staking rewards that accrued during the rebalancing process, the pool may not perfectly balanced. This is completely normal.

Set Preferred Deposit / Withdraw Validator

Since a stake pool accepts deposits to any of its stake accounts, and allows withdrawals from any of its stake accounts, it could be used by malicious arbitrageurs looking to maximize returns each epoch.

For example, if a stake pool has 1000 validators, an arbitrageur could stake to any one of those validators. At the end of the epoch, they can check which validator has the best performance, deposit their stake, and immediately withdraw from the highest performing validator. Once rewards are paid out, they can take their valuable stake, and deposit it back for more than they had.

To mitigate this arbitrage, a stake pool staker can set a preferred withdraw or deposit validator. Any deposits or withdrawals must go to the corresponding stake account, making this attack impossible without a lot of funds.

Let's set a preferred deposit validator stake account:

$ spl-stake-pool set-preferred-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR deposit --vote-account EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Signature: j6fbTqGJ8ehgKnSPns1adaSeFwg5M3wP1a32qYwZsQjymYoSejFUXLNGwvHSouJcFm4C78HUoC8xd7cvb5iActL

And then let's set the preferred withdraw validator stake account to the same one:

$ spl-stake-pool set-preferred-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR withdraw --vote-account EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Signature: 4MKdYLyFqU6H3311YZDeLtsoeGZMzswBHyBCRjHfkzuN1rB4LXJbPfkgUGLKkdbsxJvPRub7SqB1zNPTqDdwti2w

At any time, they may also unset the preferred validator:

$ spl-stake-pool set-preferred-validator Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR withdraw --unset
Signature: 5Qh9FA3EXtJ7nKw7UyxmMWXnTMLRKQqcpvfEsEyBtxSPqzPAXp2vFXnPg1Pw8f37JFdvyzYay65CtA8Z1ewzVkvF

The preferred validators are marked in the list command:

$ spl-stake-pool list Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Stake Pool: Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Pool Token Mint: BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Preferred Deposit Validator: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Preferred Withdraw Validator: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
...

User Examples

List validator stake accounts

In order to deposit into the stake pool, a user must first delegate some stake to one of the validator stake accounts associated with the stake pool. The command-line utility has a special instruction for finding out which vote accounts are already associated with the stake pool.

$ spl-stake-pool list Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Stake Pool: Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Pool Token Mint: BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
Preferred Deposit Validator: 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk
Epoch Fee: 3/100 of epoch rewards
Withdrawal Fee: none
Stake Deposit Fee: none
SOL Deposit Fee: none
SOL Deposit Referral Fee: none
Stake Deposit Referral Fee: none
Reserve Account: EN4px2h4gFkYtsQUi4yeCYBrdRM4DoRxCVJyavMXEAm5   Available Balance: ◎10.006848640
Vote Account: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ      Balance: ◎35.000000000  Last Update Epoch: 8
Vote Account: J3xu64PWShcMen99kU3igxtwbke2Nwfo8pkZNRgrq66H      Balance: ◎35.000000000  Last Update Epoch: 8
Vote Account: 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk      Balance: ◎35.000000000  Last Update Epoch: 8
Total Pool Stake: ◎115.006848640
Total Pool Tokens: 115.00684864
Current Number of Validators: 3
Max Number of Validators: 1000

Deposit SOL

Stake pools accept SOL deposits directly from a normal SOL wallet account, and in exchange mint the appropriate amount of pool tokens.

$ spl-stake-pool deposit-sol Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 100
Using existing associated token account DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ to receive stake pool tokens of mint BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB, owned by 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Signature: 23CptpZaq33njCpJPAvk8XS53xXwpfqF1sGxChk3VDB5mzz7XPKQqwsreun3iwZ6b51AyHqGBaUyc6tx9fqvF9JK

In return, the stake pool has minted us new pool tokens, representing our share of ownership in the pool. We can double-check our stake pool account using the SPL token command-line utility.

$ spl-token balance BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
100.00000000

Withdraw SOL

Stake pools allow SOL withdrawals directly from the reserve and into a normal SOL wallet account, and in exchange burns the provided pool tokens.

$ spl-stake-pool withdraw-sol Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 7VXPpSxneL6JLj18Naw2gkukXtjBZfbmPh18cnoUCMD8 2
Signature: 4bqZKUUrjVspqTGqGqX4zxnHnJB67WbeukKUZRmxJ2yFmr275CtHPjZNzQJD9Pe7Q6mSxnUpcVv9FUdAbGP9RyBc

The stake pool has burned 2 pool tokens, and in return, sent SOL to 7VXPpSxneL6JLj18Naw2gkukXtjBZfbmPh18cnoUCMD8.

You can check that the pool tokens have been burned:

$ spl-token balance BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
98.00000000

And you can check that the recipient has been credited:

$ solana balance 7VXPpSxneL6JLj18Naw2gkukXtjBZfbmPh18cnoUCMD8
2 SOL

Deposit stake

Stake pools also accept deposits from active stake accounts, so we must first create stake accounts and delegate them to one of the validators managed by the stake pool. Using the list command from the previous section, we see that 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk is a valid vote account, so let's create a stake account and delegate our stake there.

$ solana-keygen new --no-passphrase -o stake-account.json
Generating a new keypair
Wrote new keypair to stake-account.json
============================================================================
pubkey: 97wBBiLVA7fUViEew8yV8R6tTdKithZDVz8LHLfF9sTJ
============================================================================
Save this seed phrase to recover your new keypair:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
============================================================================
$ solana create-stake-account stake-account.json 10
Signature: 5Y9r6MNoqJzVX8TWryAJbdp8i2DvintfxbYWoY6VcLEPgphK2tdydhtJTd3o3dF7QdM2Pg8sBFDZuyNcMag3nPvj
$ solana delegate-stake 97wBBiLVA7fUViEew8yV8R6tTdKithZDVz8LHLfF9sTJ 38DYMkwYCvsj8TC6cNaEvFHHVDYeWDp1qUgMgyjNqZXk
Signature: 2cDjHXSHjuadGQf1NQpPi43A8R19aCifsY16yTcictKPHcSAXN5TvXZ58nDJwkYs12tuZfTh5WVgAMSvptfrKdPP

Two epochs later, when the stake is fully active and has received one epoch of rewards, we can deposit the stake into the stake pool.

$ spl-stake-pool deposit-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 97wBBiLVA7fUViEew8yV8R6tTdKithZDVz8LHLfF9sTJ
Depositing stake 97wBBiLVA7fUViEew8yV8R6tTdKithZDVz8LHLfF9sTJ into stake pool account F8e8Ympp4MkDSPZdvRxdQUZXRkMBDdyqgHa363GShAPt
Using existing associated token account DgyZrAq88bnG1TNRxpgDQzWXpzEurCvfY2ukKFWBvADQ to receive stake pool tokens of mint BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB, owned by 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Signature: 45x2UtA1b49eBPtRHdkvA3k8JneZzfwjptNN1kKQZaPABYiJ4hSA8qwi7qLNN5b3Fr4Z6vXhJprrTCpkk3f8UqgD

The CLI will default to using the fee payer's Associated Token Account for stake pool tokens and the withdraw authority on the deposited stake account.

Alternatively, you can create an SPL token account yourself and pass it as the token-receiver for the command, and specify the withdraw authority on the stake account using the withdraw-authority flag.

$ spl-stake-pool deposit-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 97wBBiLVA7fUViEew8yV8R6tTdKithZDVz8LHLfF9sTJ --token-receiver 34XMHa3JUPv46ftU4dGHvemZ9oKVjnciRePYMcX3rjEF --withdraw-authority authority.json
Depositing stake 97wBBiLVA7fUViEew8yV8R6tTdKithZDVz8LHLfF9sTJ into stake pool account F8e8Ympp4MkDSPZdvRxdQUZXRkMBDdyqgHa363GShAPt
Signature: 4AESGZzqBVfj5xQnMiPWAwzJnAtQDRFK1Ha6jqKKTs46Zm5fw3LqgU1mRAT6CKTywVfFMHZCLm1hcQNScSMwVvjQ

In return, the stake pool has minted us new pool tokens, representing our share of ownership in the pool. We can double-check our stake pool account using the SPL token command-line utility.

$ spl-token balance BoNneHKDrX9BHjjvSpPfnQyRjsnc9WFH71v8wrgCd7LB
10.00000000

Note on stake deposit fee

Stake pools have separate fees for stake and SOL, so the total fee from depositing a stake account is calculated from the rent-exempt reserve as SOL, and the delegation as stake.

For example, if a stake pool has a stake deposit fee of 1%, and a SOL deposit fee of 5%, and you deposit a stake account with 10 SOL in stake, and .00228288 SOL in rent-exemption, the total fee charged is:

total_fee = stake_delegation * stake_deposit_fee + rent_exemption * sol_deposit_fee
total_fee = 10 * 1% + .00228288 * 5%
total_fee = 0.100114144

Update

Every epoch, the network pays out rewards to stake accounts managed by the stake pool, increasing the value of pool tokens minted on deposit. In order to calculate the proper value of these stake pool tokens, we must update the total value managed by the stake pool every epoch.

$ spl-stake-pool update Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Signature: 2rtPNGKFSSnXFCb6MKG5wHp34dkB5hJWNhro8EU2oGh1USafAgzu98EgoRnPLi7ojQfmTpvXk4S7DWXYGu5t85Ka
Signature: 5V2oCNvZCNJfC6QXHmR2UHGxVMip6nfZixYkVjFQBTyTf2Z9s9GJ9BjkxSFGvUsvW6zc2cCRv9Lqucu1cgHMFcVU

If another user already updated the stake pool balance for the current epoch, we see a different output.

$ spl-stake-pool update Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR
Update not required

If no one updates the stake pool in the current epoch, all instructions, including deposit and withdraw, will fail. The update instruction is permissionless, so any user can run it before interacting with the pool. As a convenience, the CLI attempts to update before running any instruction on the stake pool.

If the stake pool transient stakes are in an unexpected state, and merges are not possible, there is the option to only update the stake pool balances without performing merges using the --no-merge flag.

$ spl-stake-pool update Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR --no-merge
Signature: 5cjdZG727uzwnEEG3vJ1vskA9WsXibaEHh7imXSb2S1cwEYK4Q3btr2GEeAV8EffK4CEQ2WM6PQxawkJAHoZ4jsQ
Signature: EBHbSRstJ3HxKwYKak8vEwVMKr1UBxdbqs5KuX3XYt4ppPjhaziGEtvL2TJCm1HLokbrtMeTEv57Ef4xhByJtJP

Later on, whenever the transient stakes are ready to be merged, it is possible to force another update in the same epoch using the --force flag.

$ spl-stake-pool update Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR --force
Signature: 5RneEBwJkFytBJaJdkvCTHFrG3QzE3SGf9vdBm9gteCcHV4HwaHzj3mjX1hZg4yCREQSgmo3H9bPF6auMmMFTSTo
Signature: 1215wJUY7vj82TQoGCacQ2VJZ157HnCTvfsUXkYph3nZzJNmeDaGmy1nCD7hkhFfxnQYYxVtec5TkDFGGB4e7EvG

Withdraw stake

Whenever the user wants to recover their SOL plus accrued rewards, they can provide their pool tokens in exchange for an activated stake account.

Let's withdraw active staked SOL in exchange for 5 pool tokens.

$ spl-stake-pool withdraw-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 5
Withdrawing ◎5.000000000, or 5 pool tokens, from stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Creating account to receive stake 5GuAyPAt6577HoGhSVRNBv6aHohVtjQ8q7q5i3X1p4tB
Signature: 5fzaKt5MU8bLjJRgNZyEktKsgweSQzFRpubCGKPeuk9shNQb4CtTkbgZ2X5MmC1VRDZ3YcCTPdtL9sFpXYfoqaeV

The stake pool took 5 pool tokens, and in exchange the user received a fully active stake account, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ. Let's double-check the status of the stake account:

$ solana stake-account 5GuAyPAt6577HoGhSVRNBv6aHohVtjQ8q7q5i3X1p4tB
Balance: 5.00228288 SOL
Rent Exempt Reserve: 0.00228288 SOL
Delegated Stake: 5 SOL
Active Stake: 5 SOL
Delegated Vote Account Address: EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Stake Authority: 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn
Withdraw Authority: 4SnSuUtJGKvk2GYpBwmEsWG53zTurVM8yXGsoiZQyMJn

Note: this operation cost the user some funds, as they needed to create a new stake account with the minimum rent exemption in order to receive the funds. This allows the user to withdraw any amount of stake pool tokens, even if it is not enough to cover the stake account rent-exemption.

Alternatively, the user can specify an existing uninitialized stake account to receive their stake using the --stake-receiver parameter.

$ spl-stake-pool withdraw-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR  --amount 0.02 --vote-account EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ --stake-receiver CZF2z3JJoDmJRcVjtsrz1BKUUGNL3VPW5FPFqge1bzmQ
Withdrawing ◎5.000000000, or 5 pool tokens, from stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Signature: 2xBPVPJ749AE4hHNCNYdjuHv1EdMvxm9uvvraWfTA7Urrvecwh9w64URCyLLroLQ2RKDGE2QELM2ZHd8qRkjavJM

By default, the withdraw command uses the token-owner's associated token account to source the pool tokens. It's possible to specify the SPL token account using the --pool-account flag.

$ spl-stake-pool withdraw-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 5 --pool-account 34XMHa3JUPv46ftU4dGHvemZ9oKVjnciRePYMcX3rjEF
Withdrawing ◎5.000000000, or 5 pool tokens, from stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Creating account to receive stake CZF2z3JJoDmJRcVjtsrz1BKUUGNL3VPW5FPFqge1bzmQ
Signature: 2xBPVPJ749AE4hHNCNYdjuHv1EdMvxm9uvvraWfTA7Urrvecwh9w64URCyLLroLQ2RKDGE2QELM2ZHd8qRkjavJM

By default, the withdraw command will withdraw from the largest validator stake accounts in the pool. It's also possible to specify a specific vote account for the withdraw using the --vote-account flag.

$ spl-stake-pool withdraw-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR  --amount 5 --vote-account EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Withdrawing ◎5.000000000, or 5 pool tokens, from stake account 3k7Nwu9jUSc6SNG11wzufKYoZXRFgxWamheGLYWp5Rvx, delegated to EhRbKi4Vhm1oUCGWHiLEMYZqDrHwEd7Jgzgi26QJKvfQ
Creating account to receive stake CZF2z3JJoDmJRcVjtsrz1BKUUGNL3VPW5FPFqge1bzmQ
Signature: 2xBPVPJ749AE4hHNCNYdjuHv1EdMvxm9uvvraWfTA7Urrvecwh9w64URCyLLroLQ2RKDGE2QELM2ZHd8qRkjavJM

Note that the associated validator stake account must have enough lamports to satisfy the pool token amount requested.

Special case: exiting pool with a delinquent staker

With the reserve stake, it's possible for a delinquent or malicious staker to move all stake into the reserve through decrease-validator-stake, so the pool tokens will not gain rewards, and the stake pool users will not be able to withdraw their funds.

To get around this case, it is also possible to withdraw from the stake pool's reserve, but only if all of the validator stake accounts are at the minimum amount of 0.001 SOL + stake account rent exemption.

$ spl-stake-pool withdraw-stake Zg5YBPAk8RqBR9kaLLSoN5C8Uv7nErBz1WC63HTsCPR 5 --use-reserve
Withdrawing ◎5.000000000, or 5 pool tokens, from stake account J5XB7mWpeaUZxZ6ogXT57qSCobczx27vLZYSgfSbZoBB
Creating account to receive stake 51XdXiBSsVzeuY79xJwWAGZgeKzzgFKWajkwvWyrRiNE
Signature: yQH9n7Go6iCMEYXqWef38ZYBPwXDmbwKAJFJ4EHD6TusBpusKsfNuT3TV9TL8FmxR2N9ExZTZwbD9Njc3rMvUcf

Appendix

Activated stakes

As mentioned earlier, the stake pool only processes active stakes. This feature maintains fungibility of stake pool tokens. Fully activated stakes are not equivalent to inactive, activating, or deactivating stakes due to the time cost of staking. Otherwise, malicious actors can deposit stake in one state and withdraw it in another state without waiting.

Transient stake accounts

Each validator gets one transient stake account, so the staker can only perform one action at a time on a validator. It's impossible to increase and decrease the stake on a validator at the same time. The staker must wait for the existing transient stake account to get merged during an update instruction before performing a new action.

Reserve stake account

Every stake pool is initialized with an undelegated reserve stake account, used to hold undelegated stake in process of rebalancing. After the staker decreases the stake on a validator, one epoch later, the update operation will merge the decreased stake into the reserve. Conversely, whenever the staker increases the stake on a validator, the lamports are drawn from the reserve stake account.

Safety of Funds

One of the primary aims of the stake pool program is to always allow pool token holders to withdraw their funds at any time.

To that end, let's look at the three classes of stake accounts in the stake pool system:

validator stake: active stake accounts, one per validator in the pool
transient stake: activating or deactivating stake accounts, merged into the reserve after deactivation, or into the validator stake after activation, one per validator
reserve stake: inactive stake, to be used by the staker for rebalancing

Additionally, the staker may set a "preferred withdraw account", which forces users to withdraw from a particular stake account. This is to prevent malicious depositors from using the stake pool as a free conversion between validators.

When processing withdrawals, the order of priority goes:

preferred withdraw validator stake account (if set)
validator stake accounts
transient stake accounts
reserve stake account

If there is preferred withdraw validator, and that validator stake account has any SOL, a user must withdraw from that account.

If that account is empty, or the preferred withdraw validator stake account is not set, then the user must withdraw from any validator stake account.

If all validator stake accounts are empty, which may happen if the stake pool staker decreases the stake on all validators at once, then the user must withdraw from any transient stake account.

If all transient stake accounts are empty, then the user must withdraw from the reserve.

In this way, a user's funds are never at risk, and always redeemable.

Transaction sizes

The Solana transaction processor has two important limitations:

size of the overall transaction, limited to roughly 1 MTU / packet
computation budget per instruction

A stake pool may manage hundreds of staking accounts, so it is impossible to update the total value of the stake pool in one instruction. Thankfully, the command-line utility breaks up transactions to avoid this issue for large pools.

Overview​

Quick Start​

Motivation​

Operation​

Fees​

Funding restrictions​

Background​

Source​

Security Audits​

Command-line Utility​

Configuration​

Current Configuration​

Cluster RPC URL​

Default Keypair​

Run Locally​

Stake Pool Manager Examples​

Create a stake pool​

Create a restricted stake pool​

Set manager​

Set fee​

Set referral fee​

Set staker​

Set Funding Authority​

Stake Pool Staker Examples​

Add a validator to the pool​

Remove validator stake account​

Rebalance the stake pool​

Decrease validator stake​

Increase validator stake​

Set Preferred Deposit / Withdraw Validator​

User Examples​

List validator stake accounts​

Deposit SOL​

Withdraw SOL​

Deposit stake​

Note on stake deposit fee​

Update​

Withdraw stake​

Special case: exiting pool with a delinquent staker​

Appendix​

Activated stakes​

Transient stake accounts​

Reserve stake account​

Safety of Funds​

Transaction sizes​