Configuring Emacs Overlay correctly through Nix Flakes

Hello, I recently started developing a highly reproduceable development environment configuration using NIxos. I ,however, run into an issue when trying to add my personal emacs config to the server and have it build the dependecies for emacs through my init.el. For example below is a screenshot of what the first few lines of my Init.el looks like:

and I receive the following error when attmepting to instal my flake:

and this is how I have configured emacs-overlay to be propagated in my nix.flakes:

and below is how I pass my init.el file to the startupscript in my emacs.nix:

I am sure some of my file naming conventions may not be standard but I am also learning through this experience so please excuse my inexperience if this is a trivial thing to do. Ideally, I would like to have NIxos build emacs from the init.el file like I do when I install emacs on my Ubuntu work laptop for example by cloning my init.el to my .emacs.d directory and running “emacs --debug-init” in cli which then builds emacs and checks the packages are installed and loaded. How can I configure NIxos such that it also builds emacs from the script?