To cite package ‘Rapp’ in publications use:

  Kalinowski T (2026). _Rapp: Easily Build Command Line Applications_.
  R package version 0.4.0, <https://CRAN.R-project.org/package=Rapp>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {Rapp: Easily Build Command Line Applications},
    author = {Tomasz Kalinowski},
    year = {2026},
    note = {R package version 0.4.0},
    url = {https://CRAN.R-project.org/package=Rapp},
  }