This reads as if written by someone who has never used these tools before. No one ever tries to "fit" the entire project into a single context window. Successfully using coding LLMs involves context management (some of which is now done by the models themselves) so that you can isolate the issues you're currently working on, and get enough context to work effectively. Working on enormous codebases over the past two months, I have never had to remind the model what it changed in another file, because 1) it has access to git and can easily see what has changed, and 2) I work with the model to break down projects into pieces that can be worked on sequentially. And keep in mind, this the worst this technology will ever be - it will only get larger context windows and better memory from here.