# Upgrading a parachain in chopsticks

You need to:
0) Run chopsticks with the relay chain and the parachain you want
1) Create an extrinsic on the parachain you want that's `system::authorizeUpgrade(hash)` with the hash of the new wasm. You can hash the file in the PJS Apps UI if needed
2) Create an extrinsic on the relay that's `xcmPallet::send()` that sends the following message to the parachain you want to upgrade: [UnpaidExecution, Transact(Superuser, enough_weight, call)] with the previous call
3) Note the preimage in the relay chain. Call `preimage::note_preimage(previous call)`
4) Use the following PJS script to make the scheduler dispatch that preimage:

import { ApiPromise, WsProvider } from '@polkadot/api';

const api = await ApiPromise.create({
    provider: new WsProvider(<your websocket endpoint>)
});
// get current block number.
const number = (await api.rpc.chain.getHeader()).number.toNumber();
// use chopsticks dev_setStorage to inject the call into the scheduler state for the next block. 
await api.rpc('dev_setStorage', {
  scheduler: {
    agenda: [
      [
        [number + 1], [
          {
            call: {
              Lookup: {
                hash: <preimage hash from step 3>,
                len: <preimage length from step 3 (not the hash length)>
              }
            },
            origin: {
              system: 'Root'
            }
          }
        ]
      ]
    ]
  }
});
// Make a block to include the extrinsic
await api.rpc('dev_newBlock', { count: 1 });

5) Check that `system::authorizedUpgrade` has the hash you want. You can do that in PJS Apps -> Chain state
6) Call `system::applyAuthorizedUpgrade` with the wasm directly on the parachain
7) ???
8) Profit