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Documentation Index

Fetch the complete documentation index at: https://docs.kynesys.xyz/llms.txt

Use this file to discover all available pages before exploring further.

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Crosschain SWAP

RubicBridge is a thin SDK client for the node-side Rubic bridge integration. It exposes two methods — getTrade for quoting a swap, and executeTrade for committing it — both of which proxy through the connected DEMOS RPC.

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How to SWAP from one chain to another

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1. Connect to the network

import { Demos, RubicBridge } from "@kynesyslabs/demosdk/websdk"
import {
    BridgeTradePayload,
    SupportedChains,
} from "@kynesyslabs/demosdk/bridge"

const rpc = "https://node2.demos.sh"
const demos = new Demos()
await demos.connect(rpc)
await demos.connectWallet(mnemonic)

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2. Create a RubicBridge instance

RubicBridge is stateless — there are no constructor arguments. The chain and payload are passed per call. 
const bridge = new RubicBridge()

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3. Build the trade payload

BridgeTradePayload.amount and the chain IDs refer to the source chain’s native units, not Demos OS. For example, an EVM swap of 10 USDT uses amount: 10 because Rubic itself handles the on-chain decimal conversion. 
// Swap 10 USDT from Polygon (chain 137) to Ethereum (chain 1).
const payload: BridgeTradePayload = {
    fromToken: "USDT",
    toToken: "USDT",
    amount: 10,
    fromChainId: 137,
    toChainId: 1,
}
Valid fromToken / toToken values are "NATIVE", "USDC", and "USDT". "NATIVE" refers to the source chain’s native token (e.g. ETH on Ethereum, MATIC on Polygon) — not Demos DEM. SupportedChains is exported as a string-valued object with these keys: 
export const SupportedChains = {
    ETH: "ETH",
    POLYGON: "POLYGON",
    BSC: "BSC",
    AVALANCHE: "AVALANCHE",
    OPTIMISM: "OPTIMISM",
    ARBITRUM: "ARBITRUM",
    LINEA: "LINEA",
    BASE: "BASE",
    SOLANA: "SOLANA",
}
The first argument to getTrade / executeTrade is the source chain key (SupportedChains.POLYGON in this example).

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4. Quote the trade

const trade = await bridge.getTrade(
    demos,
    SupportedChains.POLYGON,
    payload,
)
getTrade returns the standard RPCResponse. Inspect trade.response for the quoted route and pricing before committing.

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5. Execute the trade

If the quote looks good, commit the swap with executeTrade. The same payload is passed — there is no separate “trade object” to forward. 
const receipt = await bridge.executeTrade(
    demos,
    SupportedChains.POLYGON,
    payload,
)
The result wraps the source-chain transaction hash, e.g. 
"0x2342692074a7484f3ac9713d36cd23fdc1c51810d03639e5cf651bfefb62fdc3"
PolygonScan
For local development against an unfunded source chain, RubicBridge.executeMockTrade(demos, chain, wrappedTrade) accepts a WrappedCrossChainTrade (from rubic-sdk) and exercises the same RPC path without broadcasting on the foreign chain.