Based on my 9+ years of experience as a Unity developer, I believe I'm a perfect fit for your project. I have extensive knowledge and expertise in setting up Unity with Xcode, which is exactly what you need right now. My skills aren't just limited to setting up projects - I'm also proficient in resolving build errors and optimizing various platforms such as Android, iOS, and WebGL, among others.
Additionally, my experience includes developing both 2D and 3D games using Unity. This means that I can tackle any challenges faced during the setup process promptly and creatively. Moreover, having dealt with similar compatibility issues before, I have a profound understanding of choosing the correct version of Unity that would perfectly synchronize with your current Xcode version.
Finally, my broad skill set beyond Unity - such as payment gateway integration, social media platform implementation (including analytics), terrain design, AI implementation, blockchain - demonstrates my versatility as a developer. Thus, even after successfully resolving your current problems, I can continue to provide further assistance if needed. So let's join forces and embark on solving these build errors together!