AggLayer

The AggLayer creates a single, shared liquidity pool and state environment across all connected chains. This eliminates the need for fragmented, chain-specific liquidity and complex bridging. Key mechanisms include:

• Unified Proving: A single ZK proof validates state transitions from all connected chains.
• Atomic Composability: Smart contracts can interact across chains in a single atomic transaction, as if they were on the same network.

Enables transactions and smart contract calls that depend on the state of multiple chains to execute atomically and in a single block. This solves the asynchronous bridging problem common in other interoperability solutions.

• Example: A user can swap tokens on Chain A and immediately use them in a DeFi protocol on Chain B within the same transaction, with guaranteed execution.

The protocol is secured by a decentralized network of participants, not a single centralized entity.

• Sequencers: Order and batch transactions from connected chains.
• Provers: Generate ZK proofs (Zero-Knowledge proofs) that cryptographically verify the correctness of all state transitions in a batch.
• This architecture ensures censorship resistance and liveness for the entire aggregated ecosystem.

Provides a seamless user and developer experience by abstracting away the underlying blockchain complexity.

• For Users: A single wallet and gas token (e.g., ETH) can be used across all connected chains.
• For Developers: Enables building applications that leverage the best features of multiple execution environments (EVM, WASM, etc.) without managing cross-chain infrastructure.

Security is derived from the verification of ZK proofs on a base settlement layer (e.g., Ethereum). The validity of the entire aggregated state is reduced to the verification of a single, succinct proof on the L1.

• This provides strong cryptographic security guarantees inherited from the underlying settlement layer.
• It is more capital-efficient than traditional bridging, which often requires overcollateralization.

The AggLayer is designed as a modular protocol where any blockchain with a compatible state transition function and ability to generate ZK proofs can connect.

• It supports EVM chains, WASM chains, and other VMs.
• The connection process is permissionless, allowing for an open, evolving ecosystem of interconnected sovereign chains and rollups.

The AggLayer's core function is to aggregate liquidity and state from connected chains into a single, shared pool. This eliminates the need for fragmented liquidity pools and bridging assets, enabling:

• Atomic composability: Applications can interact with assets and contracts on any connected chain in a single transaction.
• Shared security: Leverages the underlying security of the AggLayer's base chain (e.g., Polygon PoS).
• Unified user experience: Users interact with a single, cohesive network rather than managing multiple chains.

Unlike monolithic L2s, the AggLayer connects sovereign chains (like Polygon CDK chains) that maintain their own execution environments, governance, and data availability. This provides:

• Developer sovereignty: Teams choose their virtual machine (EVM, SVM, Move), throughput, and fee models.
• Horizontal scalability: The network's capacity scales with each new connected chain.
• Modular flexibility: Chains can use different data availability layers (e.g., Celestia, Avail, EigenDA) while remaining interconnected.

The protocol enables synchronous composability, meaning transactions that span multiple chains are executed as if they were on one chain. This is a key differentiator from asynchronous bridges. Key mechanisms include:

• ZK Proof Finality: Chains submit state proofs to the AggLayer, which verifies and orders them.
• Atomic Transactions: A single user transaction can trigger actions across several chains with guaranteed execution or rollback.
• Unified Prover Network: A decentralized network of provers generates proofs for all connected chains, streamlining verification.

The AggLayer is designed to power next-generation omnichain decentralized applications. Examples include:

• Unified DEXs: A single decentralized exchange that offers liquidity from every connected chain without bridging.
• Cross-Chain Gaming: Game assets and logic can exist on optimized, app-specific chains while interacting seamlessly.
• Enterprise DeFi: Financial institutions can deploy on compliant, private chains that still interoperate with public DeFi liquidity.
• Unified Wallets: Users have one balance and address across the entire aggregated network.

The AggLayer's security and interoperability are built on Zero-Knowledge (ZK) proofs. Each connected chain uses a ZK rollup or validium framework (like Polygon CDK) to produce validity proofs of its state transitions. These proofs are:

• Posted to the AggLayer: Creating a canonical, verifiable record of all chain states.
• Aggregated: Multiple proofs can be batched into a single proof for efficiency.
• Verified on L1: The final aggregated proof is verified on the base settlement layer (e.g., Ethereum), ensuring the entire network's security is rooted in Ethereum.

The AggLayer represents a distinct approach in the interoperability landscape:

• vs. Bridging: Bridges are asynchronous and custodial/non-custodial connectors. The AggLayer provides synchronous, native interoperability.
• vs. Monolithic L2s: Single chains (e.g., Arbitrum, Optimism) scale vertically. The AggLayer scales horizontally by connecting many chains.
• vs. Cosmos IBC: IBC connects sovereign chains with light client verification. The AggLayer uses a unified ZK proof system for faster finality and shared security from a base chain.
• vs. Polkadot Parachains: Parachains share security via a central relay chain. AggLayer chains are more sovereign, choosing their own security and data availability.

The AggLayer enables atomic composability across connected chains, allowing a single transaction to interact with smart contracts and assets on multiple chains simultaneously. This eliminates the need for bridging and wrapping assets for cross-chain interactions. For example, a user could swap an asset on Chain A for an asset on Chain B and use it in a DeFi protocol on Chain C within one atomic transaction, with shared liquidity accessible across the entire network.

Developers can build sovereign chains or rollups (like Polygon CDK chains) that natively interoperate with the entire AggLayer ecosystem. This removes the complexity of building and maintaining custom bridges. Key benefits include:

• Single State Root: A unified proof system provides a single source of truth for the connected network.
• Standardized Messaging: Built-in, secure cross-chain communication primitives.
• Focus on dApp Logic: Developers concentrate on their application rather than interoperability infrastructure.

Users interact with the multi-chain ecosystem as if it were a single chain. This eliminates the fragmented experience of managing multiple wallets, RPCs, and bridges for different networks. Core UX improvements:

• Single Wallet Connection: Users can sign transactions that span multiple chains without switching networks manually.
• Unified Gas Experience: Potential for abstracted transaction fees, though specifics are implementation-dependent.
• Seamless Asset Movement: Assets are programmatically accessible across chains without manual bridging steps.

The AggLayer facilitates horizontal scalability by allowing transactions to be processed in parallel across multiple connected chains while maintaining atomic guarantees for interdependent operations. This is a shift from monolithic scaling to a modular, interconnected system. Different chains can optimize for specific use cases (e.g., high-throughput gaming, secure DeFi), and the AggLayer coordinates their execution, enabling greater total throughput than a single chain.

Connected chains (typically ZK rollups) submit validity proofs to the AggLayer, which aggregates them into a single proof. This proof aggregation creates a cryptographic guarantee of correctness for the entire network's state transitions. The security model relies on the cryptographic security of the underlying proof systems (like STARKs or SNARKs) rather than a new economic consensus, providing strong security for cross-chain operations.

The AggLayer is designed to be chain-agnostic, aiming to connect not only Polygon-based chains (e.g., Polygon zkEVM) but also external chains and rollups from other ecosystems. This positions it as a potential universal interoperability layer, reducing ecosystem fragmentation. The goal is to create a network where value and data can flow freely between Ethereum, Polygon, and other L2s/L1s, forming a cohesive "Internet of Value."

The AggLayer's core security promise is atomic composability across connected chains. It uses a shared state root (the AggState) to which all chains commit. A unified bridge and proof aggregation ensure that a transaction involving assets on multiple chains either succeeds entirely or fails entirely, preventing partial execution risks. This eliminates the bridging and liquidity fragmentation problems of traditional multi-chain ecosystems.

Security is anchored by the Polygon Plonky2 prover, which generates ZK proofs (SNARKs) for all connected chain states. These proofs are aggregated and verified on the AggLayer's base settlement layer (initially Ethereum L1). The model assumes the data availability (DA) of the connected chains—for a ZK rollup, its data must be posted to a secure DA layer (like Ethereum) for the AggLayer's state commitments to be valid and enforceable.

The security is not monolithic but a composition of the underlying chains' security. Key assumptions include:

• Settlement Layer Security: The base layer (e.g., Ethereum) must be secure and live.
• Chain Honesty: Each connected chain must honestly submit its state proofs.
• Sequencer Decentralization: The central AggLayer sequencer is a potential liveness/centralization point; its decentralization is a roadmap goal. Economic security is derived from the cumulative value secured by all connected chains and the cost to attack the base settlement layer.

A key security upgrade over existing models is the replacement of isolated, hack-prone bridges with a unified bridge managed by the AggLayer. This reduces the attack surface from N*(N-1)/2 potential bridge contracts to a single, formally verified entry/exit point. Users interact with a canonical bridge per chain, which then coordinates with the AggLayer's shared state, significantly mitigating bridge exploit risks that have plagued interoperability.

The current design has a single sequencer operated by Polygon Labs, creating a liveness dependency and potential censorship vector. The roadmap includes decentralizing this component. For censorship resistance, if the AggLayer sequencer is unresponsive, users can fall back to withdrawing assets via the underlying chain's own bridge or dispute mechanisms, though this breaks atomic composability and reverts to slower, asynchronous withdrawals.

As a nascent protocol, the AggLayer's contracts and logic are likely to be upgradeable, managed by a multisig or similar mechanism controlled by Polygon Labs initially. This introduces admin key risk. Long-term security depends on a credible path to decentralized governance and potentially immutable core contracts. Users must trust the upgrade process not to introduce malicious changes or confiscate funds.

A proposed component for future AggLayer versions, a shared sequencer would be a decentralized network that orders transactions across all connected chains. This prevents MEV fragmentation and ensures atomic composability—where a transaction on Chain A and Chain B are processed in the same block as a single, unified operation—without relying on a central entity.

This is the primary user-facing benefit enabled by the AggLayer. By providing a single, cryptographically verified state root for all connected chains, it creates the illusion of a single liquidity pool spread across multiple execution environments. This eliminates the need for traditional bridges and wrapping of assets, allowing native assets to move between chains with minimal latency and without fragmented security models.