Introduction

Current overview of Ingot Protocol on Tondi

Introduction

What is Ingot?

Ingot is Tondi's asset layer for inscriptions, fungible assets, collectibles, and settlement-oriented objects. It uses Pay2Ingot outputs on Layer 1 and an off-chain ordering layer to turn valid transactions into coherent asset history.

The current direction of Ingot is built around a clear split of responsibilities:

  • L1 authenticates spending, enforces basic transaction validity, and provides data availability.
  • L2 indexers and clients reconstruct ordered state, apply schema logic, and resolve application history.

Instead of forcing every use case into one storage pattern, Ingot now distinguishes between three broad state styles:

  • Commit for anchored definitions, durable fingerprints, and collectible-style assets
  • Flow for lightweight transfers, MIMO activity, and high-frequency application traffic
  • Vault for balance-oriented settlement where stronger asset conservation and policy control matter

Why choose Ingot?

The primary design goal is to make Tondi asset issuance expressive without turning Layer 1 into a bloated application engine. Ingot keeps the on-chain surface small, while leaving richer state interpretation and application rules to wallets, indexers, and higher-level protocols.

Key advantages:

  • Layered by design: keep L1 simple while letting L2 handle ordering and application semantics
  • Flexible state styles: use Commit, Flow, or Vault depending on the workload
  • Privacy-friendly: support compact authorization and private spending branches
  • DAG-aware: designed for Tondi's fast, parallel environment
  • Broad asset coverage: supports fungible assets, artifacts, multi-asset inventories, and policy-driven settlement

Key features

  • Pay2Ingot Output Type: Ingot uses a dedicated output type (ScriptPublicKey.version = 2) as the shared envelope for multiple asset styles.

  • oUTXO Coordination Layer: Ingot uses an ordered UTXO model to turn valid transactions into canonical object history, enforce one active tip, and keep replay deterministic across clients.

  • Standard Families: The current public direction is centered on standards such as IRC-20 for fungible flows, IRC-21 for anchored artifacts, and IRC-25 for multi-asset inventories and game-style objects.

  • Privacy Enhancements:

    • MAST (Merkle Abstract Syntax Trees): Hides alternative spending paths, revealing only what's necessary
    • MuSig2 Support: Group signatures blend seamlessly with individual ones, keeping collaborations private
    • Optional data anchoring: choose stronger on-chain anchoring where permanence matters and lighter witness-carried data where throughput matters

  • Flexible Locking Mechanisms: Ingot offers four straightforward ways to secure assets:

    • None: Open participation for public objects and non-custodial coordination surfaces
    • PubKey: Straightforward ownership, including team control through aggregated signatures
    • ScriptHash: Programmable authorization for richer policy logic
    • MastOnly: Privacy-first branching for more complex spending paths

  • Universal VM Support: Ingot's ScriptHash lock mechanism provides a foundation for executing code on virtually any virtual machine. This architectural flexibility means that, in the future, Ingot has the potential to realize true universal blockchain interconnection—enabling assets and contracts from Bitcoin, Ethereum, Solana, and countless other chains to interoperate seamlessly on Tondi.

  • Layer 2 Infrastructure: Ingot is a practical foundation for rollups, DA anchoring, and application-specific state systems that need Tondi settlement without moving all semantics into consensus.

Benefits to the Tondi Ecosystem

As the Tondi ecosystem continues to evolve, Ingot is positioned to significantly contribute to the growth and innovation of the Tondi ecosystem by offering several advantages:

  • Increased Adoption: Ingot gives builders a clearer path for fungible assets, collectibles, and application objects without requiring a full smart-contract account model.

  • Layer2 Infrastructure: Ingot provides a practical settlement and anchoring surface for higher-layer protocols that need ordered state and flexible data availability.

  • Seamless Integration: Ingot is designed for easy integration with the broader Tondi ecosystem, empowering developers to create cross-chain applications and utilize the protocol's features within the Tondi network. The protocol's Bitcoin compatibility (Taproot/BIP340) enables cross-chain tooling and verification.

  • Privacy and Security: Ingot's privacy-first design ensures that user activities remain protected. Multi-signature transactions are indistinguishable from single-signature ones, and MAST trees hide unused spending paths, providing strong privacy guarantees.

  • Developer-Friendly: The protocol keeps the public model compact and composable, so builders can choose the right standard family without learning a full execution environment first.

  • Ecosystem Growth: By supporting tokens, NFTs, inscriptions, DAOs, and custom applications, Ingot enables a wide range of use cases. This diversity fosters innovation and attracts different types of users and developers to the Tondi ecosystem.

Architecture Overview

The following diagram illustrates Ingot's layered architecture:

Application Layer

L2 Indexer Layer

L1 Consensus Layer

Yes

Yes

Yes

No

Transaction Output

Pay2Ingot?

IngotOutput

Schema ID

Hash Payload

Flags

Lock

MAST Root

L1 Validation

Signature/VM Check

MAST Proof

Valid?

On-Chain

Indexer

Parse Payload

Schema Router

Known Schema?

State Machine

raw_data Mode

oUTXO Rules

Single Active Tip

Spend Old Create New

Conflict Resolution

Artifact State

Wallet APIs

Explorer UIs

dApps

Architecture Overview Explanation:

This diagram illustrates Ingot's three-layer architecture, demonstrating how transactions flow from creation to application use.

Layer 1 - Consensus Layer (L1): The top layer handles on-chain validation and security. When a Pay2Ingot output is detected in a transaction, the consensus layer performs comprehensive validation:

  • Validates output structure (Schema ID, Hash Payload, Flags, Lock, MAST Root)
  • Verifies signatures and authentication proofs
  • Executes VM checks for ScriptHash locks
  • Validates MAST proofs for privacy-preserving spending paths
  • Only transactions passing all checks are accepted onto the chain

Layer 2 - Indexer Layer (L2): The middle layer processes validated Ingot outputs and maintains artifact state:

  • Parses payloads from confirmed transactions
  • Routes to appropriate schema handlers based on Schema ID
  • Executes state machines for known schemas
  • Falls back to raw_data mode for unknown schemas
  • Enforces oUTXO rules: single active tip, spend-old-create-new semantics, deterministic conflict resolution
  • Maintains consistent artifact state across the network

Layer 3 - Application Layer: The bottom layer exposes functionality to end users:

  • Wallet APIs provide asset management and transaction building
  • Explorer UIs display asset history and current state
  • dApps integrate Ingot functionality into decentralized applications

This layered design separates concerns: L1 ensures security and consensus, L2 provides rich state tracking, and the application layer delivers user-friendly interfaces.

Next: Data Insertion Mechanism