Supported Chains

11.1 Launch Chain Support

Phase 2 additions: SUI (additional), Cosmos Hub, Osmosis, Neutron
Phase 3 additions: Stellar, additional Cosmos chains

11.2 Finality Confirmation Depths (constants.py)

FINALITY_BLOCKS: dict[str, int] = {
    'ethereum':   12,   # ~2.5 min; PoS single-slot final at 2 epochs
    'arbitrum':    1,   'optimism':  1,   'base': 1,
    'polygon':    64,   'bsc':      64,
    'avalanche':   1,   # Snowman: instant after acceptance
    'solana':      1,   # Confirmed commitment level
    'sui':         1,   'stellar': 1,
    'cosmoshub':   1,   'osmosis': 1,   'neutron': 1,
}

11.3 ChainAdapter Interface

All adapters implement the same abstract interface — the only component containing ecosystem-specific code:

class ChainAdapter(ABC):
    @abstractmethod
    def get_pending_messages(self, from_height, to_height) -> list[PendingMessage]: ...

    @abstractmethod
    def is_message_delivered(self, seq_no, src_chain) -> bool: ...

    @abstractmethod
    def relay_message(self, msg, private_key, max_fee_usd) -> RelayResult: ...

    @abstractmethod
    def verify_relay(self, relay_tx, expected_seq) -> tuple[bool, raw_proof_dict]: ...

    @abstractmethod
    def get_rpc_latency_ms(self) -> float: ...

    @abstractmethod
    def get_wallet_info(self, private_key) -> WalletInfo: ...

    @abstractmethod
    def get_current_height(self) -> int: ...

Ecosystem-specific implementations:

• EVMAdapter — handles all 7 EVM chains via web3.py. PoA chains (Polygon, BNB) get ExtraDataToPOAMiddleware injected automatically.
• SolanaAdapter — uses solana-py and the Anchor IDL. Parses base64-encoded Anchor events using discriminators.
• SUIAdapter — uses SUI JSON-RPC API via aiohttp. Object-centric execution via programmable transaction blocks.
• StellarAdapter — split architecture: base ledger via Horizon REST API, smart contracts via Soroban RPC.
• CosmosAdapter — uses Cosmos REST API (Stargate) and CosmWasm execution. Handles per-chain denom differences.