• Package number in the form <major>.<minor>.<patch> or <major>.<minor>.<patch>.<dev>
    • See principles at
    • Major version when you make incompatible API changes
    • Minor version when you add functionality in a backward compatible manner
    • Patch version when you make backward compatible bug fixes
    • Other engagement rules: see e.g. BioconductoR
  • Parsed and compared by base::package_version()
  • Forms the basis of dependency checking

The topic of version numbering will come up again later in Chapter 21.