Skip to main content
CONFIDENTIAL & PROPRIETARY © 2025 Inkwell Finance, Inc. All Rights Reserved. This document is for informational purposes only and does not constitute legal, tax, or investment advice, nor an offer to sell or a solicitation to buy any security or other financial instrument. Any examples, structures, or flows described here are design intent only and may change.

​
Overview

Embedded Lending is built on the same core Leviathan infrastructure — Solana programs for lending logic, Sui for policy enforcement, and EVM contracts for revenue capture — with additional modules that scope capital to a single integrating protocol. This page describes the on-chain modules, the integration flow, and the security model at a high level.

​
On-Chain Modules

┌────────────────────────────────────────────────────────┐
│                  Leviathan Core (Solana)                │
│                                                        │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐  │
│  │ Embedded Loan│  │ Credit Line  │  │  Agreement   │  │
│  │  Lifecycle   │  │  (Pre-Auth)  │  │   Bridge     │  │
│  └──────┬───────┘  └──────┬───────┘  └──────┬───────┘  │
│         │                 │                 │          │
│  ┌──────▼───────┐  ┌──────▼───────┐  ┌──────▼───────┐  │
│  │ Function     │  │  Protocol    │  │  Splitter    │  │
│  │   Gate       │  │  Whitelist   │  │  Registry    │  │
│  └──────────────┘  └──────────────┘  └──────────────┘  │
└────────────────────────────────────────────────────────┘

​
Embedded Loan Lifecycle

Manages the full lifecycle of an embedded loan — origination, activation, repayment tracking, and completion. This module operates within the leviathan-core program but scopes the loan to a single protocol’s sandbox. Key differences from standard loans:
  • The loan is bound to a specific protocol whitelist at creation
  • Policy parameters are derived from the protocol’s approved function set
  • Completion or default triggers protocol-specific settlement flows

​
Credit Line (Pre-Authorization)

Enables pre-approved borrowing limits for users who meet credit criteria. Rather than applying for individual loans, users receive a credit line that they can draw against as needed within the protocol.
  • Credit limits are determined by the user’s on-chain score from leviathan-score
  • Drawing against the credit line creates individual loan positions
  • The credit line can be revoked or adjusted based on ongoing behavior

​
Function Gate

Restricts which smart contract functions borrowed capital can interact with. This is the core caging mechanism that ensures capital stays within the protocol’s approved operations.
  • Each protocol defines an approved function set during onboarding
  • Every transaction signed with borrowed capital is checked against the gate
  • Transactions targeting non-approved functions are rejected before signing
Function-level gating goes beyond simple address whitelisting — a borrower might be approved to call swap() on a DEX contract but blocked from calling withdraw() on the same contract.

​
Protocol Whitelist

Maintains the set of approved protocol destinations — contract addresses, program IDs, and account structures that borrowed capital is permitted to interact with.
  • Configured during protocol onboarding
  • Immutable for the duration of individual loans
  • Shared across all embedded loans for a given protocol integration

​
Agreement Bridge

Links legal agreements to on-chain loan state using cryptographic hashes. This extends the InkPact system to embedded contexts, ensuring that the terms governing a user’s credit line are verifiable on-chain.
  • Agreement documents are hashed and stored alongside loan accounts
  • Both parties can independently verify term accuracy
  • Supports protocol-specific agreement templates

​
Splitter Registry

Manages revenue split configurations for embedded loans. Each protocol integration has a registered splitter configuration that determines how revenue flows between the borrower, the protocol, and loan repayment.
  • Split ratios are set during protocol onboarding
  • Individual loans inherit the protocol’s splitter configuration
  • Revenue oracles report split events back to the loan account

​
Integration Flow

The end-to-end flow from protocol onboarding through loan completion: 
┌─────────────┐     ┌─────────────┐     ┌─────────────┐
│  Protocol   │     │    User     │     │   Revenue   │
│  Onboards   │     │ Pre-Qualifies│    │   Splits    │
│             │     │             │     │   Begin     │
│ • Whitelist │     │ • Credit    │     │             │
│ • Functions │     │   scoring   │     │ • Auto      │
│ • Splitter  │     │ • Agreement │     │   repayment │
│ • Agreement │     │ • Credit    │     │ • Oracle    │
│   template  │     │   line set  │     │   reports   │
└──────┬──────┘     └──────┬──────┘     └──────┬──────┘
       │                   │                   │
       ▼                   ▼                   ▼
┌─────────────┐     ┌─────────────┐     ┌─────────────┐
│    Loan     │     │   Capital   │     │  Repayment  │
│  Originated │     │   Caged to  │     │  or         │
│             │     │   Protocol  │     │  Completion │
│ • Terms set │     │             │     │             │
│ • Policy    │     │ • Function  │     │ • Cap       │
│   bound     │     │   gating    │     │   reached   │
│ • Capital   │     │ • Tx verify │     │ • Loan      │
│   deployed  │     │ • Session   │     │   closed    │
│             │     │   keys      │     │             │
└─────────────┘     └─────────────┘     └─────────────┘
  1. Protocol Onboards — the protocol registers its contract set, approved functions, and revenue split configuration with Leviathan
  2. User Pre-Qualifies — the user’s credit score is assessed via leviathan-score, and a credit line is established with protocol-specific agreement terms
  3. Loan Originated — when the user draws on their credit line, a loan position is created with policy parameters derived from the protocol’s configuration
  4. Capital Caged — borrowed capital is deployed into a policy-gated environment where it can only interact with the protocol’s approved functions. Every transaction is verified by leviathan-verifier
  5. Revenue Splits — as the user generates revenue through protocol activity, splitter contracts automatically direct a portion to loan repayment
  6. Completion — once the repayment cap is reached, the loan closes and all restrictions are lifted

​
Security Model

​
Function-Level Gating

The function gate is the primary security mechanism for embedded loans:
  • Pre-signing verification — every transaction is checked against the approved function set before it reaches the dWallet signing flow
  • Defense in depth — the leviathan-verifier program provides an independent validation layer, parsing transaction calldata to confirm policy compliance
  • No bypass path — there is no mechanism to override or relax the function gate during an active loan

​
Capital Isolation

Borrowed capital is isolated to the integrating protocol through multiple enforcement layers:
LayerEnforcement
Function GateOnly approved functions on approved contracts
Policy dWalletThreshold signing rejects non-compliant transactions
Transaction VerifierIndependent calldata parsing and validation
Session Key ScopeEphemeral keys scoped to protocol-specific operations

​
Revenue Oracle Integrity

Revenue split events on EVM chains are reported back to Solana via oracle attestations:
  • Oracle operators submit cryptographically signed attestations
  • The core program validates attestation signatures before updating loan state
  • Stale or invalid attestations are rejected

​
Integration Points

​
SDK Client

The @leviathan/sdk/embedded subpath exports the EmbeddedLendingClient, which provides:
  • Credit line eligibility checks
  • Agreement creation and signing
  • Loan origination and drawdown
  • Capital usage validation
  • Splitter management and revenue tracking

​
On-Chain Programs

Embedded Lending uses all four Leviathan Solana programs:
ProgramRole in Embedded
leviathan-coreEmbedded loan lifecycle, function gate, protocol whitelist
leviathan-poolCapital sourcing from lending pools
leviathan-scoreUser credit assessment and pre-qualification
leviathan-verifierTransaction validation against protocol function set

​
Revenue Oracle

A dedicated revenue oracle monitors splitter contract events on EVM chains and reports repayment progress to the Solana loan account. The oracle is configured per-protocol during onboarding.