zk Cross-chain Latest (September 11, 2025)

Here we report on the progress of the leading builders in the ZK Cross-Chain ecosystem, documenting recent significant releases, technical breakthroughs and general updates.

Featuring: @Agglayer, @PolyhedraZK, @AcrossProtocol, @union_build, @Orbiter_Finance, & @ZekoLabs

Agglayer

Tech

@0xPolygon's @Agglayer introduced Agglayer CDK Enterprise - a privacy-first blockchain stack designed for enterprises: https://agglayer.dev/blogs/agglayer-cdk-enterprise-financial-grade-privacy-meets-native-interop-for-custom-blockchains 

CDK Enterprise allows launching permissioned EVM chains with financial-grade privacy and seamless upgrade paths from Hyperledger Besu. It combines private network controls - like ACLs, identity tools, and private explorers - with Agglayer connectivity for future interoperability. 

Built on the high-performance Erigon client, it aims to enable scalable, secure, and auditable deployments without compromising cost-efficiency or network effects.

Interoperability

Agglayer has launched the Agglayer Developer Portal, offering a local environment for testing and building crosschain applications: https://agglayer.dev/blogs/introducing-agglayer-developer-portal 

Developers can simulate multiple connected chains using the AggSandbox, access example apps, and explore network data. The Portal simplifies crosschain development with tools, SDKs, and tutorials - aiming to reduce fragmentation and prepare teams to deploy seamlessly across the growing Agglayer network.

Polyhedra

Tech

@PolyhedraZK shared its latest development update, outlining progress across GPU integration, codebase simplification, and recursive verifier enhancements: https://x.com/PolyhedraZK/status/1962452953450836070

Key highlights include:

• GPU CI Integration: Added GitHub CI for MSM-related tests with GPU and NVCC setup on GitHub runners.
• Bi-KZG Disablement: Removed the bivariate KZG implementation to streamline the codebase and focus on GPU-accelerated unikzg.
• ZKML Recursive Verifier: Introduced integration with updated circuits and a new verification function.
• New Submodule: Added zkcuda_recursion with components needed for recursive verifier functionality.
• Circuit Refactoring and Testing: Updated circuit creation across the codebase and conducted end-to-end testing, with debugging and optimization of larger circuits underway.
  

The project also reported key upgrades to Expander, improving performance and reliability:

• GPU Prover Integration: Full integration allows smooth switching between CPU and GPU with no additional setup, streamlining workflows.
• FPGA Arithmetic Primitives: Optimized adders and multipliers for Versal HBM devices support multiple fields with improved throughput.
• Field-Specific Optimization: Early benchmarks confirmed functional accuracy and efficiency, preparing for broader hardware acceleration in proof generation.

Across

Integrations

@AcrossProtocol has been integrated into @optimexfi to enable crosschain swaps between native @Bitcoin and leading EVM networks, including @arbitrum, @Optimism, @base, and @BNBCHAIN: https://across.to/blog/optimex 

The system keeps BTC secured on the Bitcoin blockchain while Across executes fast, low-cost transfers on the EVM side. This setup lets users maintain full custody of their Bitcoin and access DeFi markets with efficient, predictable, and trust-minimized transactions.

The project has also launched on @solana, enabling fast, low-cost, and secure bridging between @ethereum and Solana: https://across.to/blog/solana 

With over $27 billion in volume and 17 million transactions processed, Across brings its intent-based architecture to support seamless interoperability. The bridge currently supports USDC transfers, using Circle’s CCTP for rebalancing, and connects not only Solana and Ethereum but also major L2s, aiming to expand liquidity and long-term multichain growth.

Union

@union_build announced support for @base, linking the network into its ZK interoperability layer: https://union.build/blog/base 

The integration enables secure, trustless liquidity and crosschain communication, giving Base access to IBC, MoveVM, and other environments. 

Union’s ZK cryptography and consensus verification aims to strengthen security while improving app-level connections and state proofs.

Orbiter Finance

@Orbiter_Finance announced several new integrations including:

@juchain101: Integrated as a high-performance L1 focused on on-chain traffic and user growth. Users can now bridge $ETH and $USDT to JuChain via Orbiter: https://x.com/Orbiter_Finance/status/1955178166160666633

@hemi_xyz: Added support for Hemi, a modular protocol for scaling and interoperability. Bridging of $BTC and $USDC to Hemi is now live through Orbiter: https://x.com/Orbiter_Finance/status/1955265072160444863

@aergo_io: Partnered as HPP’s official cross-chain bridge provider. This integration enables seamless transfers of $ETH, $USDC, and $HPP to the HPP Mainnet, unlocking cross-chain AI-native DeFi, trading strategies, and access to intelligent agent ecosystems: https://x.com/Orbiter_Finance/status/1960643452829647308

@Conflux_Network: Integrated Conflux Network, a L1 focused on transforming stablecoin and payment infrastructure. Users can bridge $ETH, $BTC, $USDT, and $USDC to Conflux via Orbiter for frictionless consumer payment experiences: https://x.com/Orbiter_Finance/status/1961368470404440138

Zeko

Zeko Labs has launched its upgraded testnet, inviting developers to begin building zkApps using the platform’s new features: https://x.com/ZekoLabs/status/1956062350743671272

Key improvements include higher throughput, parallel proving, rollup bridging, instant transaction confirmations, and dynamic fees. Developers can access setup guides and full release notes to start testing and deploying on the enhanced infrastructure. 

Full details are available in Zeko’s documentation and GitHub: https://github.com/zeko-labs/zeko/releases