What is the roadmap for based appchains?
What is the roadmap for based appchains?

How do synchronously composable transactions work?
How do synchronously composable transactions work?
Pylon runs a node for the settlement chain you are deployed to as well as the sequencing node for your appchain and any other appchains in your Sync Zone. Pylon then detects whenever there is a transaction calling into another chain through a Port Contract. It forwards the call to the other chain and then injects the results back into the originating Port contract with a Priming Transaction that frontruns the original application call to ensure the data is available to complete the call. See the Architecture page for detailed mechanics, or Build Onchain for practical usage examples.
How can I trust the data being injected into the port contract?
How can I trust the data being injected into the port contract?
We are working on a TEE based proof process that will ensure data moving across chains is verifiably correct with the speed to ensure a seamless experience. We will be releasing more about this soon!
What are the trust assumptions for the chain itself?
What are the trust assumptions for the chain itself?
We currently run a reth stack based system. So the trust assumptions for the chain are fraud proof based and of course impacted by the parent chain you deploy on. Due to the requirement for coordinated sequencing within a Sync Zone and the current architecture all appchain sequencers within a Sync Zone run on a single node. Standard nodes for a given appchain (such as for submitting fraud proofs) can be operated by anyone.
What stacks/settlement chains are supported?
What stacks/settlement chains are supported?
Currently we support any op-stack settlement chains but are working on adding support for additional chains. Even if your targeted settlement chain is not already supported we’d love to speak with you about getting your use-case supported. Please reach out through the Spire contact form.
What fees are there?
What fees are there?
Please reach out to discuss through the Spire contact form!
How does Pylon differ from traditional bridges?
How does Pylon differ from traditional bridges?
Traditional bridges are asynchronous and create execution gaps where operations can fail between chains. Pylon enables synchronous composability, meaning cross-chain operations are atomic - they either all succeed or all fail together. This eliminates oracle risks, execution gaps, and complex state management that plague traditional bridge solutions.
Can I deploy my existing dApp to Pylon?
Can I deploy my existing dApp to Pylon?
Yes! Pylon is EVM-compatible, so you can deploy existing Solidity contracts with minimal modifications. The main difference is that you can now add cross-chain functionality by reading from settlement layer contracts using Port Contracts and forwarding proxies. See our Quickstart guide for examples.
What happens if the coordinator goes down?
What happens if the coordinator goes down?
The coordinator is a critical component for synchronous composability. If it goes down, new cross-chain operations cannot be processed, but existing appchain functionality continues to work normally. We’re working on decentralization improvements to reduce this single point of failure.
How do I get testnet ETH for development?
How do I get testnet ETH for development?
Reach out via the Spire contact form. Include your wallet address and a brief description of your use case; we typically fund accounts within 24–48 hours.
What's the difference between Pylon and other appchain platforms?
What's the difference between Pylon and other appchain platforms?
Pylon’s key differentiator is synchronous composability - the ability to interact with settlement layer contracts atomically. Other appchain platforms require complex bridge integrations and async handling. Pylon makes cross-chain development feel like single-chain development.
How do I migrate from an existing L2 to Pylon?
How do I migrate from an existing L2 to Pylon?
Migration depends on your specific use case. For new applications, start fresh with Pylon to take advantage of synchronous composability. For existing applications, you can gradually migrate by adding cross-chain functionality while maintaining your existing deployment. Contact us through the Spire contact form to discuss your migration strategy.
What programming languages and frameworks are supported?
What programming languages and frameworks are supported?
Pylon supports all standard EVM tooling:
- Solidity - Primary smart contract language
- Foundry - Development framework and testing
- Hardhat - Alternative development framework
- Web3.js/Ethers.js - JavaScript libraries
- All EVM wallets - MetaMask, WalletConnect, etc.
How do I get support or report issues?
How do I get support or report issues?
- GitHub Issues - For bug reports and feature requests
- Discord Community - For general questions and discussions
- Application Form - For access requests and business inquiries
- Documentation - Comprehensive guides and examples