> The amalgamation file is more than 180,000 lines long and over 6 megabytes in size.

Yes, but the article also says that file is generated by a makefile from more than a hundred .c and .h files, and that it's done for ease of distribution and because optimizers do better with a single compilation unit.

It's not like the authors spend a lot of time working on the amalgamation and that's the way the project is developed.

To be fair, only 125,367 lines of that is actual c.