Update cabal build instructions using project

Author: philderbeast

README.md

@@ -66,24 +66,20 @@ builder using either nix or cabal. Directions for both are given below:
 ### Manually Building the Site With Cabal
 
 If you don't have nix installed, or if you are inside of the project's nix
-shell, you will want to use cabal to compile the builder. To do so, enter the
-`builder` directory and compile the program with:
+shell, you will want to use cabal to compile the builder, the only package in
+the project.
 
 ```shell
-cabal v2-build
+$ cabal build all
 ```
 
-Once compiled, the builder must be run from the project root directory so that
-it can find all of the content. To run the builder, you need to first find the
-name of the executable. From the builder directory, you can find the executable
-path by running:
+Once compiled, execute the builder from the project root directory so that it
+can find all of the content.
 
 ```
-cabal v2-exec -- which haskell-org-site
+$ cabal exec haskell-org-site build
 ```
 
-Using that path, you can run the builder from the project root directory.
-
 ### Manually Building the Site With Nix
 
 If you have nix installed, you can have nix build the builder by running: