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"), method_to_url: [ eth_call: System.get_env("ETHEREUM_JSONRPC_TRACE_URL"), eth_getBalance: System.get_env("ETHEREUM_JSONRPC_TRACE_URL"), trace_replayTransaction: System.get_env("ETHEREUM_JSONRPC_TRACE_URL") ], http_options: [recv_timeout: :timer.minutes(1), timeout: :timer.minutes(1), 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") ], variant: EthereumJSONRPC.Parity ]