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

# Spark

> Supply assets to SparkLend money markets or deposit into Spark Savings vaults, and hold the resulting receipt token.

Spark covers two distinct yield types under one provider: **SparkLend**, a pooled money market (public `type` `lending`), and **Spark Savings**, a set of ERC-4626 vaults (public `type` `vault`) anchored to the Sky Savings Rate. They have separate mechanics and separate yield IDs; check a yield's `type` before assuming which one you're looking at.

## Availability

**SparkLend** (lending): Ethereum only. You supply a reserve asset and earn the variable rate paid by borrowers. Yield IDs follow `{token}-sparklend`, for example `ethereum-usdc-sparklend`. The position token is an `sp`-prefixed receipt (for example `spUSDC`), mechanically the same as an Aave aToken: pegged 1:1, balance grows as interest accrues.

**Spark Savings** (vault): ERC-4626 vaults that deposit into the Sky Savings Rate.

| Version | Networks | Position token |
| - | - | - |
| Savings V2 | Ethereum, Robinhood Chain | Vault share (for example `spUSDC`, `spETH`) |
| Savings V1 (legacy) | Ethereum, Base, Arbitrum, Optimism, Unichain | Vault share (for example `sUSDC`) |

Query [`GET /v1/yields?providers=spark`](/api-reference/YieldsController_getYields) for the exact set of markets and vaults enabled for your project; SparkLend and both Savings versions share the `spark` provider ID.

## Entering

**SparkLend**: enter takes a required `amount`. yield.xyz builds an approval transaction (skipped if allowance already covers the amount) followed by the supply transaction; the aToken-style receipt is minted in the same transaction.

**Spark Savings**: enter follows the generic ERC-4626 deposit flow, approval then deposit, minting vault shares 1:1 in value at the time of deposit.

## Exiting

**SparkLend**: exit takes an optional `amount` and a `useMaxAmount` flag to redeem the full balance. There is no cooldown.

**Spark Savings**: exit redeems vault shares for the underlying asset through the standard ERC-4626 withdraw flow. There is no cooldown.

## Rewards and position

SparkLend's public `rewardRate` reflects Aave-style variable interest computed from the reserve's on-chain utilization, distributed each block with automatic claiming.

For Savings V2 vaults, `rewardRate` is read from the vault's on-chain variable savings rate (VSR) and annualized. The legacy Savings V1 sUSDC-style vaults price through the Sky Savings Rate instead: on deposit the vault swaps USDC to USDS 1:1 through the Sky Peg Stability Module and back on withdrawal, with no slippage beyond network fees. Both versions claim rewards automatically; there is no manual claim step for either.

<Note>
  Deposits into Spark Savings vaults also earn Spark Points, an off-chain loyalty accrual tracked by Spark rather than a yield.xyz reward token or balance.
</Note>

## Next steps

<Columns cols={2}>
  <Card title="Lending" icon="hand-holding-dollar" href="/documentation/earn/defi/lending/index">
    Compare all supported lending protocols.
  </Card>

  <Card title="Action lifecycle" icon="arrows-rotate" href="/documentation/earn/core-concepts/actions">
    How enter and exit actions progress from creation to settlement.
  </Card>
</Columns>


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