Polygon says Agglayer Bali testnet settled value between Ethereum and Miden in both directions, making Miden the first chain without Ethereum-style architecture to clear the bridge. Miden is a private ZK-native chain with client-side proving and note-based state, so the integration needed new bridge primitives and proof circuitry while keeping Agglayer’s pessimistic-proof security model. The pitch is institutional: public Polygon chains, private CDK chains, and protocol-private Miden can all route through one bridge to unified liquidity, with mainnet bridging and more assets beyond ETH next.

TLDR by @Benthic