[informatimago]

Big programs are made by writing a lot of small programs. Any other way fails.

This is about the only result of software engineering.

I would advice more small programs, but perhaps with the perspective to gather them in bigger programs: sicp

https://mitpress.mit.edu/sicp/

also comes in video:

https://www.youtube.com/watch?v=2Op3QLzMgSY&list=PLB63C06FAF...

http://htdp.org/