zline

Fast, modern, and flexible pure-Zsh prompt engine.
A streamlined replacement for Powerlevel10k with zero subshell forks, Base16 palette harmony, and declarative array configuration.

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Highlights

• ⚡ Sub-Millisecond Synchronous Rendering: Renders prompts in under 0.7 ms with 0 subshell forks on the critical path.
• 📦 100% Pure Zsh: Zero compiled C++ daemons or binary downloads. Runs anywhere Zsh 5.8+ is installed (macOS, Linux, BSDs, Alpine/musl, Termux).
• 🧩 Declarative Array Syntax: Replaces 1,600 lines of uppercase global environment variables (POWERLEVEL9K_*) with concise, composable Zsh arrays.
• 🎨 Base16 / Term16 Palette First: Standardizes on ANSI 0–15 colors, adapting harmoniously to any terminal theme (Catppuccin, Tokyo Night, Gruvbox, Nord, Dracula).
• 📁 Smart Path Shortening: Intermediate directory shortening (~/s/g/c/zline), tail shortening (--last 2), path aliases, project root anchoring, and custom formatters.
• 🌿 Two-Phase Git Status: Synchronous branch detection in 0.07 ms + non-blocking background worker with granular per-state icons (--staged-icon, --ahead-icon).
• 🛠️ 58 Built-In Segments: Rich ecosystem covering cloud (AWS, GCP, Azure, K8s, Terraform, Docker, Helm, Pulumi), runtimes (Node, Bun, Deno, Rust, Go, Python, Ruby, PHP, Java, .NET, Lua, Zig, Elixir, Crystal, Haskell, Scala, Kotlin, Swift, Dart, Julia, OCaml, Clojure, Erlang, Perl, R, Solidity), build tools (CMake, Meson, Bazel), version control (Git, Jujutsu / jj), environments (Mise, Nix, Direnv, OS/Distro, Containers, Shell Depth), text badges (text), modal editing (Vi-Mode), system metrics (RAM, Load, Battery), and universal .tool-versions detection.
• 🚀 Instant Prompt (< 0.1 ms): Pre-compiled static snapshot displayed immediately upon terminal launch before .zshrc finishes executing.
• 🧼 Transient Prompt: Automatically collapses multi-line prompts down to a minimal ❯ symbol on Enter, keeping your terminal scrollback pristine.
• 🌐 Modern Terminal Protocols: Native OSC 133 semantic shell integration, OSC 7 directory inheritance, OSC 8 hyperlinks, and OSC 777 / OSC 9 long-command desktop notifications.

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Quickstart

1. With zload (Recommended)

# In ~/.zshrc
plugins=(
  casonadams/zline
)
zload "${plugins[@]}"

zline preset powerline --transient
zline init

2. Manual Installation

git clone https://github.com/casonadams/zline.git ~/.zline

Add to your ~/.zshrc:

source ~/.zline/zline.zsh

zline preset powerline --transient

zline_left=(
  'dir --shorten 1 --alias github.com=gith --anchor git'
  'git --clean 2 --dirty 3'
  newline
  prompt_char
)

zline_right=(
  'status --hide-zero'
  'exec_time --min 2'
)

zline init

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Visual Presets & Curated Themes

zline includes built-in structural layout presets and curated color themes:

Layout Presets

Preset	Description	Command
Powerline	Multi-colored background blocks with Powerline arrow glyphs (, )	zline preset powerline
Lean	Modern, flat, space-separated layout with crisp foreground colors	zline preset lean
Rainbow	High-contrast vivid blocks for rapid visual parsing	zline preset rainbow
Pure	Minimalist two-line prompt inspired by Sindre Sorhus's Pure prompt	zline preset pure

Curated Color Themes

Theme	Description	Command
Catppuccin	Soothing pastel palette based on Mocha	zline preset catppuccin
Tokyo Night	Dark, vibrant aesthetic inspired by Tokyo nightlife	zline preset tokyonight
Nord	Arctic, north-bluish clean palette	zline preset nord
Gruvbox	Warm retro groove color scheme	zline preset gruvbox

List all presets with zline preset list or inspect preset code with zline preset show <name>.

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Performance Benchmarks

Measured on macOS (Apple Silicon arm64, Zsh 5.9):

============================================================
              zline Performance Benchmarks                  
============================================================

Benchmark                        Iterations       Per Op     Target   Status
-------------------------------- ---------- ------------ ---------- --------
Sync Prompt Render (Powerline)         1000      0.66 ms  < 1.50 ms     PASS
Sync Prompt Render (Lean)              1000      0.52 ms  < 1.00 ms     PASS
Directory Shortening & Anchor          1000      0.10 ms  < 0.15 ms     PASS
Synchronous Git HEAD Reader            1000     0.072 ms  < 0.15 ms     PASS
Instant Prompt Load                     500     0.057 ms  < 0.50 ms     PASS
============================================================
ALL BENCHMARKS PASSED!

Run benchmarks locally:

zsh benchmark/bench.zsh

Run quality linting and specification verification gates:

./scripts/lint
zsh test/verify_all.zsh

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Documentation

• Configuration Syntax
• Built-in Segments Reference
• Styling & Base16 Colors
• Event Hooks & Extensibility
• Migrating from Powerlevel10k
• Unix Manual Page (man zline)

Web Documentation: https://casonadams.github.io/zline/

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License

MIT © Cason Adams