As a seasoned Full Stack Developer with a specific focus on backend systems, I am no stranger to Linux servers and their configurations, including firewall setup and NAT support. My fluency in Ubuntu, the chosen Linux distribution for your project, coupled with my extensive knowledge of server configuration, puts me in a prime position to handle this task diligently.
Furthermore, my background features proven expertise in REST API integration and ensuring system security. I am well acquainted with RESTful paradigms and have skillfully integrated them into various projects. This will enable me to effectively configure your server in such a way that it seamlessly communicates with the third-party's REST API, while maintaining utmost security at all times.
Lastly, my recent foray into the Web3 space has deeply enriched my technical skillset, making me highly adaptable to emerging technologies like those used in blockchain and decentralized applications (dApps). By selecting me for this project, you can enjoy the dual benefit of my proficiency in both your immediate needs - Linux server setup and REST API integration - as well as future-proofing your tech infrastructure to potentially leverage Web3 components if needed. Let's move forward together towards achieving a secure, high-functioning server that meets all of your business's expectations!