Powerlevel9k
Powerlevel9k was a tool for building a functional CLI
Powerlevel9k is a highly configurable Zsh prompt theme that uses “powerline” fonts to render glyph icons, separators, and status indicators. It supports a rich set of “prompt segments” (Git status, battery, time, host, SSH status, etc.) that you can enable, disable, reorder, and style. Because of its flexibility, users can create distinctive, informative prompts tailored to their workflows (e.g. show branch, ahead/behind, stashes, etc.). However, Powerlevel9k is relatively heavy in terms of prompt rendering and status checks (e.g. querying Git status), which can make it slower on large repositories or slower machines. Over time, many users migrated or forked to lighter or faster versions (e.g. Powerlevel10k) that maintain compatibility with existing configuration. Despite performance trade-offs, it remains well known for combining aesthetics and utility in the Zsh ecosystem.
So while it is not actively maintained, it remains historically important and used by some users.