Terminal
Test Runner
Simulates a watch-mode test runner: spec suites stream in with green PASS ticks, one flaky spec fails red then retries and recovers, a live pass/fail tally and per-suite timings update in real time, and the run closes with a Stmts/Branch/Funcs/Lines coverage table before restarting on a loop.
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When to use it
Developer-tool landing pages, CI/testing dashboards, loading screens, or any terminal-aesthetic hero that needs a credible "tests are running" ambient backdrop.
When not to
Light-background UIs (background is hardcoded dark #0d1117) and non-technical audiences for whom spec output and coverage percentages carry no meaning.
Working with an AI agent
Every component ships agent-ready metadata. An example instruction for this one:
Add a suite {f:'payments/refund.spec.ts', ms:190, specs:['issues a full refund','rejects a double refund']} to the suites array, change the flaky spec's assertion message, and slow the per-spec streaming from 95ms to 160ms.
Safe to edit
- suite/spec data (suites array: file names, per-suite ms, spec descriptions, flaky index)
- coverage table rows and percentages (cov array)
- per-spec / per-suite streaming delays (sleep 95/170ms and retry 280/300ms)
- max visible lines (MAX=30)
- loop restart pause (sleep 2800ms)
- accent and level colors (.ttr-ok/.ttr-warn/.ttr-err CSS)
Keep intact
- IIFE with "use strict"
- visibilitychange running-flag stop/resume guard
- prefers-reduced-motion staticFrame() early-return path
- role=img + aria-label on the wrapper and aria-hidden corner caption
- live tally element updated via tally()
Known limitations
- Background and terminal palette are hardcoded dark — must edit CSS to re-theme
- Not themeable: exposes no --pro-* custom-property block
- Purely ambient with no click interactivity
- With justify-content:flex-end older lines scroll out of view on short viewports; only the newest MAX lines render
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- Build RunnerSimulates npm install + build pipeline in a scrolling terminal; packages, lint/compile steps, and file-change events stream in sequence and loop endlessly.
- Network TraceSimulates a live traceroute — hops appear one by one with color-coded latency (green/orange/red); ms values fluctuate after trace completes, then loop.
- Diff ViewerA unified git diff viewer that streams a code review in line by line: a file header with +12/-4 counts, a hunk header, then context/addition/deletion…