As such, Nightingale's engine is based on the Mozilla XULRunner with libraries such as the GStreamer media framework and libtag providing media tagging and playback support, amongst others.

[3] Users can add features and change functionality in Nightingale by installing extensions.

[4] Community coded extensions are available on The Nightingale Addons Page Archived 2020-09-29 at the Wayback Machine.

Skins are referred to as "feathers" in Nightingale, and give users and artists the ability to change the look of Nightingale via an extension which generates a default skin.

Using CSS (and optionally XUL), and an image manipulation program such as Photoshop or GIMP, users are then able to make Nightingale look however they want.