Polygon AggLayer goes live, unifying liquidity across 2 chain layers

Polygon's AggLayer mainnet went live July 18, connecting the network's proof-of-stake sidechain with custom-built chains through a shared liquidity layer. The infrastructure upgrade allows assets and data to move between Polygon Chain and chains built using the Polygon Chain Development Kit without requiring separate bridges for each connection.

"AggLayer creates a unified liquidity environment where users can move assets across connected chains without the fragmentation that typically occurs when multiple networks operate independently," according to the AggLayer technical documentation published by Polygon Labs.

Polygon Chain, which launched its proof-of-stake mainnet in 2020, processes transactions using its Bor execution layer and Heimdall-v2 consensus client, with POL serving as the native gas and staking token. Chains built with Polygon CDK — infrastructure for launching dedicated Ethereum-compatible networks — connect to AggLayer by default, giving them access to cross-chain messaging and shared interoperability infrastructure. The AggLayer design uses proof aggregation to settle transactions across connected chains without requiring each network to maintain its own bridge contracts. POL, which replaced MATIC in a 1:1 migration on Sept. 4, 2024, has an initial supply of 10 billion tokens with an annual emission rate of about 2% after June 2025, with newly minted tokens distributed to staking rewards and the community treasury.

The launch marks a structural shift for Polygon's ecosystem strategy. Rather than operating a single scaling network, Polygon now positions AggLayer as the interoperability backbone connecting multiple chains. This directly addresses the liquidity fragmentation problem that has limited cross-chain activity in decentralized finance, where the same asset often sits in isolated pools across separate networks. Polygon's proof-of-stake chain has supported payments, DeFi applications, gaming, and NFT projects since its 2020 mainnet launch, and the AggLayer extends that reach to custom chains built by institutions, game developers, and enterprises. The AggLayer launch follows the sunset of Polygon zkEVM, a separate ZK rollup network that Polygon Labs shut down July 3 after determining the sidechain-plus-AggLayer architecture better served the ecosystem's long-term goals.

The AggLayer positions Polygon to compete more directly with other Ethereum scaling networks such as Arbitrum and Optimism, which use optimistic rollup architectures rather than Polygon's sidechain-plus-interoperability approach. Unlike those networks, which publish transaction data to Ethereum for verification, Polygon Chain relies on its own validator set and anchors periodic checkpoints to Ethereum. The AggLayer's proof aggregation model aims to offer a middle path — faster execution than Ethereum mainnet with cross-chain connectivity that rollup networks have struggled to achieve without third-party bridges. For developers building on Polygon CDK, the AggLayer eliminates the need to bootstrap separate liquidity pools, potentially lowering the barrier to launching new blockchain applications.

This article is for informational purposes only and does not constitute investment advice.