SkoolKit
SkoolKit is a collection of utilities that can be used to disassemble a Spectrum game (or indeed any piece of Spectrum software written in machine code) into a format known as a skool file. Then, from this skool file, you can use SkoolKit to create a browsable disassembly in HTML format, or a re-assemblable disassembly in ASM format. So the skool file is - from start to finish as you develop it by organising and annotating the code - the common ‘source’ for both the reader-friendly HTML version of the disassembly, and the developer- and assembler-friendly ASM version of the disassembly.
I mainly want this for bin2sna.py, as I want to fiddle around with some Z80 development for the Spectrum and Spectrum Next using z80asm, which is a bit barebones by itself.