use Mix.Config config :explorer, json_rpc_named_arguments: [ transport: EthereumJSONRPC.HTTP, transport_options: [ http: EthereumJSONRPC.HTTP.HTTPoison, url: "https://sokol.poa.network", method_to_url: [ eth_getBalance: "https://sokol-trace.poa.network", trace_replayTransaction: "https://sokol-trace.poa.network" ], http_options: [recv_timeout: 60_000, timeout: 60_000, hackney: [pool: :ethereum_jsonrpc]] ], variant: EthereumJSONRPC.Parity ]