Byline simplifies writing interactive command-line applications by building upon ansi-terminal and haskeline. This makes it possible to print messages and prompts that include terminal escape sequences (such as setting text colors) that are automatically disabled when standard input is a file. It also means that Byline works on both POSIX-compatible systems and on Windows. The primary features of Byline include printing messages, prompting for input, and generating custom menus. It was inspired by the highline Ruby library and the terminal library by Craig Roche.