📝Open source makes systems more extensible

Access to the source code allows small modifications without re-implementing the whole application from scratch.

Open source promotes reuse. Creating a spin-off in open source is called “Fork.”

Examples:

• Vim / Neovim
• XEmacs was a fork of Emacs but (I believe) contributed many ideas back into Emacs itself
• Emacs (What makes Emacs extensible?)
• Linux distros
  • Everybody can create a Linux distro and there are tons of them
• ErgoDox and its variants
• ffmpeg as an extensible media pipeline