Looking for an expert to build a NodeJS + Mail Server (Send & Receive) Socket API [Ubuntu] + Build Automation

DO NOT APPLY FOR THIS JOB, UNLESS YOU HAVE AN IDEA, SUGGESTION(S) AND YOU ARE REALLY EXPERIENCED AND UNDERSTAND EVERYTHING WHAT I SAY WITHOUT NEED FOR (APP) PLATFORMS, ETC. THE TASK HAS TO BE COMPLETED IN 4 DAYS AT MAXIMUM. PAYMENT ONLY FOR FINISHED JOB. I DO NOT HAVE ANY TIME TO WASTE! I need help with my anonymous, autonomic network project and help would be appreciated. I tried to setup nodemailer's wildduck (nodejs mail server), but could not, it did not work and after thinking that I am build an open peer-to-peer network, using mongodb to store mails instead of e.g. postfix (binary code mailstore), or using some kind of Docker is not the best idea, so I should make e.g. a postfix server on my server so my nodejs backend reads a certain e-mail. I have to automate this process so the network automatically purchases more servers anonymously from bulletproof hosting providers, but also later supports public user nodes. So, what I need help [which I can pay for] is building e.g. postfix socket API + connect NodeJS into it so I can find an exact message send for certain user @ [domain] + timestamp : [last 1 min], unless you have better suggestions like running .sh script [chmod 777] from nodejs as a Promise (maybe unsecure way to do it) and then receiving the message after it is translated from binary code to human-readable format. I am using Ubuntu VPS from one little (privacy-friendly) hosting provider. If you know better mail server than Postfix for me, you can use it. Building the mail server and connection between nodejs has to be easily automated(*), meaning that another server BUILD the mail server and the socket api / connection with nodejs on another server. The mail server + nodejs will work on the same server, though. (*) The automated building job (e.g. .sh, nodejs and puppeteer) will be for someone (else) later, but you have to make it easy for him to automate the build process (installing mail server through .sh script and setting up the socket for nodejs to use + launching nodejs [clone] on the other server). THIS ALSO MEANS I HAVE TO KNOW (AFTERWARDS) EVERY STEP ABOUT HOW YOU INSTALLED THE MAIL SERVER AND THE SOCKET API [500 USD PAYMENT], UNLESS YOU CREATE THE AUTOMATIC BUILDER (+ NODEJS "LAUNCHER") YOURSELF [700 USD]!