use Mix.Config config :explorer, json_rpc_named_arguments: [ transport: EthereumJSONRPC.HTTP, transport_options: [ http: EthereumJSONRPC.HTTP.HTTPoison, url: System.get_env("ETHEREUM_JSONRPC_HTTP_URL") || "https://sokol.poa.network", method_to_url: [ eth_call: System.get_env("ETHEREUM_JSONRPC_TRACE_URL") || "https://sokol-trace.poa.network", eth_getBalance: System.get_env("ETHEREUM_JSONRPC_TRACE_URL") || "https://sokol-trace.poa.network", trace_replayTransaction: System.get_env("ETHEREUM_JSONRPC_TRACE_URL") || "https://sokol-trace.poa.network" ], http_options: [recv_timeout: 60_000, timeout: 60_000, hackney: [pool: :ethereum_jsonrpc]] ], variant: EthereumJSONRPC.Parity ], subscribe_named_arguments: [ transport: EthereumJSONRPC.WebSocket, transport_options: [ web_socket: EthereumJSONRPC.WebSocket.WebSocketClient, url: System.get_env("ETHEREUM_JSONRPC_WS_URL") || "wss://sokol-ws.poa.network/ws" ], variant: EthereumJSONRPC.Parity ]