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Consumers

A consumer is an app that inherits colors from its provider. It doesn’t define its own palette — it references colors by their ANSI index. What those colors actually look like depends entirely on the provider’s theme.

How Consumers Use Color

When git diff displays an addition in green, it emits ANSI escape code 32 (foreground color 2). The terminal emulator — the provider — maps color index 2 to an RGB value from its current theme. The consumer never knows what “green” actually looks like.

This is why the same git diff output looks completely different under Tokyo Night (muted teal green) vs Gruvbox (warm olive green) vs Catppuccin Mocha (pastel mint). The diff is identical; the provider’s palette is different.

Consumers in Litmus

Litmus represents consumers through fixtures — reproducible terminal scenarios that exercise specific tools. Each fixture runs a real command (git diff, cargo build, bat, etc.) and captures the output.

FixtureConsumerWhat it demonstrates
git-diffgit diffDiff colors: additions, deletions, context
cargo-buildcargo buildCompiler output: warnings, errors, notes
bat-syntaxbatSyntax-highlighted source with line numbers
ripgrep-searchrgMatch highlighting, filenames, line numbers
ls-colorls --colorFile type colors: dirs, executables, symlinks
git-loggit log --graphGraph colors and branch decorations
shell-promptbash sessionPrompt colors and command output
python-replpython3REPL output, tracebacks
htoptopCPU, memory, process table
log-viewerapp logsStructured logs: INFO/WARN/ERROR/DEBUG
color-swatchANSI paletteReference palette: 16 ANSI + 256-color
color-showcaseCI dashboardSimulated deploy pipeline using all 16 ANSI colors
editor-uitext editorSyntax highlighting, status bar, line numbers

Each fixture is captured once per (provider, theme) combination, giving you the exact pixels your terminal would display.

Why Swatches Aren’t Enough

A 16-color swatch tells you the palette. It doesn’t tell you:

  • Whether git diff additions are distinguishable from context lines
  • Whether cargo warnings are readable against the background
  • Whether bat line numbers have enough contrast
  • Whether ls directory colors clash with executable colors

These are consumer-specific questions that depend on how each app maps ANSI indices to semantic meaning. Litmus answers them by showing the actual consumer output, not abstract swatches.