examples/using-next/utils/store.js
function initMatic() {
  if (!matic) {
    matic = new Matic({
      maticProvider: process.env.MATIC_PROVIDER,
      parentProvider: process.env.PARENT_PROVIDER,
      rootChainAddress: process.env.ROOTCHAIN_ADDRESS,
      maticWethAddress: process.env.MATIC_WETH_ADDRESS,
      syncerUrl: process.env.SYNCER_URL,
      watcherUrl: process.env.WATCHER_URL,
      withdrawManagerAddress: process.env.WITHDRAWMANAGER_ADDRESS,	
    })

    matic.wallet = '<private-key>' // your private key
  }
}
function initMatic() {
  if (!matic) {
    matic = new Matic({
      maticProvider: process.env.MATIC_PROVIDER,
      parentProvider: process.env.PARENT_PROVIDER,
      rootChainAddress: process.env.ROOTCHAIN_ADDRESS,
      maticWethAddress: process.env.MATIC_WETH_ADDRESS,
      syncerUrl: process.env.SYNCER_URL,
      watcherUrl: process.env.WATCHER_URL,
      withdrawManagerAddress: process.env.WITHDRAWMANAGER_ADDRESS,	
    })

    matic.wallet = '<private-key>' // your private key
  }
}
Create sdk instance