LilyPond Contributor's Guide: 4.9 Build system

## 4.9 Build system

We currently use make and stepmake, which is complicated and only used by us. Hopefully this will change in the future.

### Version-specific texinfo macros

- made with `scripts/build/create-version-itexi.py` and
  `scripts/build/create-weblinks-itexi.py`
- used extensively in the `WEBSITE_ONLY_BUILD` version of the website (made with ‘`website.make`’, used on lilypond.org)
- not (?) used in the main docs?
- the numbers in VERSION file: MINOR_VERSION should be 1 more than the last release, VERSION_DEVEL should be the last online release. Yes, VERSION_DEVEL is less than VERSION.

#### LilyPond — Contributor’s Guide v2.22.2 (stable-branch).