Hey HN, I built TypeCrt because every typing test I tried had noticeable input lag at 150+ WPM. Monkeytype uses React. Keybr uses React. 10FastFingers feels like 2012. So I built one from scratch with vanilla TypeScript, vanilla CSS, and direct DOM manipulation — no React, no Vue, no Angular.

The result: zero perceptible input latency, even at 200+ WPM.

Some things I'm proud of:

- CRT terminal aesthetic with 50+ themes and a visual theme creator - Adaptive practice mode ("KeyForge") that uses Markov chains to generate words targeting your weakest keys - Per-word burst speed breakdown, keystroke heatmaps, consistency tracking - Command palette (Ctrl+Shift+P), mechanical keyboard sounds, pace caret ghost - Cloud sync via Firebase, tiered analytics dashboard

Tech stack: TypeScript (strict) + Vanilla CSS + Vite. ~15K lines. No dependencies beyond Chart.js and Firebase.

I'd genuinely love feedback from this community — especially on performance, UX, and what features would make you switch from your current typing tool.