SUMMARY.md is tedious to write. There is code to avoid that by automatically generating that file, an idea that solves this problem for when the book already exists. What I propose applies to when the book does not even exist.

Following is how it would look:

# Building and debugging `rustc` - How to Build and Run the Compiler - Prerequisites - Suggested Workflows - Distribution artifacts - Documenting Compiler - The compiler testing framework - Running tests - Adding new tests - Using `compiletest` commands to control test execution

That would produce the following directory structure:

building-and-debugging-rustc.md how-to-build-and-run-the-compiler/ index.md --> this implicit file is added for any chapter that has sub-chapters prerequisites.md suggested-workflows.md distribution-artifacts.md documenting-compiler.md the-compiler-testing-framework/ index.md running-tests.md adding-new-tests.md using-compiletest-commands-to-control-test-execution.md 

Is this sensible (ignoring backward compatibility concerns)?