CompactNumber
हिन्दीA K/M/B ladder is not how most of the world shortens numbers. India groups by lakh and crore; Japan and China group by ten-thousands.
What most apps ship
1.2M
`${(n / 1e6).toFixed(1)}M`
Open source · MIT · zero dependencies
React components that work anywhere.
Any device. Any network. Any language. Any ability. Built for the conditions most component libraries are never tested against, and verified against all ten of them, in CI.
866 tests passing87 componentsZero dependencies
The bugs you cannot see
Every example below is real code running in your browser right now. The left column is what most applications ship, not a strawman, the actual line people write. The right column is this library. If you only read one section, read this one.
BidiText
العربيةA right-to-left name next to a number pulls the number to the wrong side of it. Here the naive version renders the reply count before the name instead of after. The sentence reads backwards, and only for users with RTL names.
What most apps ship
إيان - 42 replies
<span>{name} - {n} replies</span>SortableTable
DeutschArray#sort compares UTF-16 code points, not letters. Accented names file after Z, and lowercase files after uppercase.
What most apps ship
Zebra · apple · Ångström · Élodie
names.sort()CurrencyField
DeutschparseFloat on a German-formatted amount silently truncates at the thousands separator. Twelve hundred euros becomes one euro twenty-three.
What most apps ship
€1.23
parseFloat("1.234,56")Ten axes, every component
Each one is a real assertion in the test suite, not a claim in this paragraph. The whole library is 110 components and 11 primitives, with nothing between them and your project.
Performance
Every item is bundled, minified, and gzipped with React external. It fails against its declared tier budget if it exceeds it.
Accessibility
axe runs over every component in every state, plus what axe cannot see: focus moving to new errors, live regions mounted before they are filled.
Internationalisation
Direction, calendar, numbering system, and week start come from the locale tag. Every string is a prop. RTL is a data change, not a rewrite.
Privacy
A source scan forbids fetch, XHR, sendBeacon, and fingerprinting APIs across the whole registry. Nothing here phones home.
Security
dangerouslySetInnerHTML, eval, and innerHTML assignment are forbidden registry-wide. sanitizeHref strips executable URL schemes.
Resilience
ErrorBoundary contains a render crash to its own subtree with an announced, focusable, recoverable fallback.
Offline
A component that makes no network calls cannot be broken by a dropped connection. ResilientForm goes further and replays.
SSR safety
Every component renders through react-dom/server in CI. No reaching for window, document, or navigator during render.
Sensory safety
Any file that animates must also reference prefers-reduced-motion, checked by the same static scan.
Supply chain
Zero runtime dependencies. react is the only permitted import anywhere in the registry, enforced in CI.
Install one, or all of them
Components are copied into your repo by the shadcn CLI. No package to depend on, no version to upgrade, nothing to remove if you change your mind.
npx shadcn@latest add https://kata-ui-rho.vercel.app/r/async-boundary.jsonMost component libraries are tested on the laptop they were written on.
~2.6 billion
are offline or intermittently connected
Requests do not fail loudly on a bad connection. They hang. The spinner spins forever, the user taps again, and now there are two orders.
~1.3 billion
live with a significant disability
The live region is created in the same tick its text appears, so no screen reader ever announces it. The code looks accessible. It is silent.
~6.5 billion
do not speak English as a first language
Layouts assume left-to-right, dates assume the Gregorian calendar, numbers assume Latin digits, and address forms assume American ones.
None of this is unknown. It is just never the default, so every team rebuilds the same handling badly, under deadline, and ships the version that worked where it was written.
Try it
Switch the network to Offline and submit the form. Your answers are kept and sent when the connection returns. Switch the language to العربية and the whole thing mirrors, including the calendar and the digits.
Nothing below is re-rendered by the switcher with different code paths. These are the same components reading the same APIs your users' browsers report.
AsyncBoundary
Four states, announced to screen readers, with height reserved so nothing jumps.
Your order shipped
3 days ago · August 29, 2026
$1,299.50
AdaptiveImage
On Save-Data or 2G it refuses to spend the user's data until they ask.
ResilientForm
Type something, then switch to Offline and press Send.
Locale facts
Direction, calendar, digits, and week start, all resolved from the tag, not hardcoded.
- Direction
- ltr
- Calendar
- gregory
- Number
- 1,234,567.89
- Date
- Saturday, August 29, 2026
Accessible, translation-ready React components engineered for slow networks, cheap phones, and screen readers. Every component is verified in CI on ten axes: performance, accessibility, internationalisation, privacy, security, resilience, offline support, SSR safety, sensory safety, and supply chain.