Linux based Application for Reading data over Modbus

Hi All, We need to have an application developed in Linux. Please note that we will be using ARM based CPU. The application will need following interfaces: 1. Modbus TCP (libmodbus) 2. MQTT (several libraries are there) 3. HTTP post (curl) The Application flow will be like this: Application will keep reading data from Modbus Slave, maintain a counter based on change in Modbus data. as soon as there is any update in the counter or periodic time(configurable) occurs, it will send data over MQTT and submit using HTTP post method. We need to keep storing the counter value just in case there is power failure. So whenever the application restarts it will start count where it has left earlier. We also need to take care that if the connectivity to http server is lost then it will store all the reporting data in internal memory, and sends all the data as soon as the connectivity is restored. The application should be robust, that means in case of any exception, it should handle properly and logs the information. We also need to log at various stages of execution so that we can use it for maintenance purpose. We are open for any programming language, but the program has to be secure safe and reliable. Any suggestions are welcome.