If you only learn one lesson from this whole book, I hope it is this: You can make your job much easier by filling you bag-of-tricks with reusable software components. Then most of your work reduces to simply putting those building blocks together to make whatever you want. It becomes child's play, like building something out of Tinker Toys.
If you do this, your job becomes more fun because you eliminate a lot of the drudgery. You don't keep solving the same old problems over an over. You use solutions you've already found for those problems, and devote most of your time to solving newer, more challenging problems. You cut down on the time you spend testing and documenting your software because many of the components have been tested and documented already.
The only way you can make this work is by learning to write independent modules. You have to hide special operational details inside a black box where they can't be seen. Start with modules that are small and simple, then build the smaller modules into bigger ones. Control the flow of information between modules by using parameter lists whenever possible.
This method works. I've used it in FORTRAN, assembly, and HPL. It works especially well in Ada, because Ada was designed to support this way of writing software. Let it work for you.