diff --git a/packages/contracts/contracts/staking/IHorizonStaking.sol b/packages/contracts/contracts/staking/IHorizonStaking.sol
new file mode 100644
index 000000000..92ebe7a33
--- /dev/null
+++ b/packages/contracts/contracts/staking/IHorizonStaking.sol
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+pragma solidity 0.7.6;
+pragma abicoder v2;
+
+interface IHorizonStaking {
+    struct Provision {
+        // Service provider that created the provision
+        address serviceProvider;
+        // tokens in the provision
+        uint256 tokens;
+        // tokens that are being thawed (and will stop being slashable soon)
+        uint256 tokensThawing;
+        // timestamp of provision creation
+        uint64 createdAt;
+        // authority to slash the provision
+        address verifier;
+        // max amount that can be taken by the verifier when slashing, expressed in parts-per-million of the amount slashed
+        uint32 maxVerifierCut;
+        // time, in seconds, tokens must thaw before being withdrawn
+        uint64 thawingPeriod;
+    }
+
+    // the new "Indexer" struct
+    struct ServiceProviderInternal {
+        // Tokens on the Service Provider stake (staked by the provider)
+        uint256 tokensStaked;
+        // Tokens used in allocations
+        uint256 __DEPRECATED_tokensAllocated;
+        // Tokens locked for withdrawal subject to thawing period
+        uint256 __DEPRECATED_tokensLocked;
+        // Block when locked tokens can be withdrawn
+        uint256 __DEPRECATED_tokensLockedUntil;
+        // tokens used in a provision
+        uint256 tokensProvisioned;
+        // tokens that initiated a thawing in any one of the provider's provisions
+        uint256 tokensRequestedThaw;
+        // tokens that have been removed from any one of the provider's provisions after thawing
+        uint256 tokensFulfilledThaw;
+        // provisions that take priority for undelegation force thawing
+        bytes32[] forceThawProvisions;
+    }
+
+    struct ServiceProvider {
+        // Tokens on the provider stake (staked by the provider)
+        uint256 tokensStaked;
+        // tokens used in a provision
+        uint256 tokensProvisioned;
+        // tokens that initiated a thawing in any one of the provider's provisions
+        uint256 tokensRequestedThaw;
+        // tokens that have been removed from any one of the provider's provisions after thawing
+        uint256 tokensFulfilledThaw;
+        // provisions that take priority for undelegation force thawing
+        bytes32[] forceThawProvisions;
+    }
+
+    struct DelegationPool {
+        uint32 __DEPRECATED_cooldownBlocks; // solhint-disable-line var-name-mixedcase
+        uint32 __DEPRECATED_indexingRewardCut; // in PPM
+        uint32 __DEPRECATED_queryFeeCut; // in PPM
+        uint256 __DEPRECATED_updatedAtBlock; // Block when the pool was last updated
+        uint256 tokens; // Total tokens as pool reserves
+        uint256 shares; // Total shares minted in the pool
+        mapping(address => Delegation) delegators; // Mapping of delegator => Delegation
+    }
+
+    struct Delegation {
+        // shares owned by the delegator in the pool
+        uint256 shares;
+        // tokens delegated to the pool
+        uint256 tokens;
+        // Timestamp when locked tokens can be undelegated (after the timelock)
+        uint256 tokensLockedUntil;
+    }
+
+    struct ThawRequest {
+        // tokens that are being thawed by this request
+        uint256 tokens;
+        // the provision id to which this request corresponds to
+        bytes32 provisionId;
+        // the address that initiated the thaw request, allowed to remove the funds once thawed
+        address owner;
+        // the timestamp when the thawed funds can be removed from the provision
+        uint64 thawingUntil;
+        // the value of `ServiceProvider.tokensRequestedThaw` the moment the thaw request is created
+        uint256 tokensRequestedThawSnapshot;
+    }
+
+    // whitelist/deny a verifier
+    function allowVerifier(address verifier, bool allow) external;
+
+    // deposit stake
+    function stake(uint256 tokens) external;
+
+    // create a provision
+    function provision(
+        uint256 tokens,
+        address verifier,
+        uint256 maxVerifierCut,
+        uint256 thawingPeriod
+    ) external;
+
+    // initiate a thawing to remove tokens from a provision
+    function thaw(bytes32 provisionId, uint256 tokens) external returns (bytes32);
+
+    // moves thawed stake from a provision back into the provider's available stake
+    function deprovision(bytes32 thawRequestId) external;
+
+    // moves thawed stake from one provision into another provision
+    function reprovision(bytes32 thawRequestId, bytes32 provisionId) external;
+
+    // moves thawed stake back to the owner's account - stake is removed from the protocol
+    function withdraw(bytes32 thawRequestId) external;
+
+    // delegate tokens to a provider
+    function delegate(address serviceProvider, uint256 tokens) external;
+
+    // undelegate tokens
+    function undelegate(
+        address serviceProvider,
+        uint256 tokens,
+        bytes32[] provisions
+    ) external returns (bytes32[]);
+
+    // slash a service provider
+    function slash(
+        bytes32 provisionId,
+        uint256 tokens,
+        uint256 verifierAmount
+    ) external;
+
+    // set the Service Provider's preferred provisions to be force thawed
+    function setForceThawProvisions(bytes32[] provisions);
+
+    // total staked tokens to the provider
+    // `ServiceProvider.tokensStaked + DelegationPool.serviceProvider.tokens`
+    function getStake(address serviceProvider) public view returns (uint256 tokens);
+
+    // staked tokens that are currently not provisioned, aka idle stake
+    // `getStake(serviceProvider) - ServiceProvider.tokensProvisioned`
+    function getIdleStake(address serviceProvider) public view returns (uint256 tokens);
+
+    // staked tokens the provider can provision before hitting the delegation cap
+    // `ServiceProvider.tokensStaked * Staking.delegationRatio - Provision.tokensProvisioned`
+    function getCapacity(address serviceProvider) public view returns (uint256);
+
+    // provisioned tokens that are not being used
+    // `Provision.tokens - Provision.tokensThawing`
+    function getTokensAvailable(bytes32 provision) public view returns (uint256 tokens);
+
+    function getServiceProvider(address serviceProvider)
+        public
+        view
+        returns (ServiceProvider memory);
+
+    function getProvision(bytes32 provision) public view returns (Provision memory);
+}