Er An Khoo
Software engineer based in Singapore. Publishes small libraries, dev tools, and hosted utilities under kea0811.
tilt-card-react
tilt-card-react is a zero-dependency React library that gives any card a 3D parallax tilt: it leans toward the pointer on desktop, follows the gyroscope on mobile, and ships a glare highlight plus a `parallax()` helper that floats child layers at their own depth. It's built as a headless `useTilt()`
tailwind-class-doctor
tailwind-class-doctor is a command-line linter for Tailwind CSS class strings that finds the rot a stylesheet linter can't see: exact duplicates (`flex flex`), same-property conflicts where only the last class survives (`p-2 p-4`), specifics left dead under a later shorthand (`pl-1 … p-2`), classes
npm-bloat-detector
npm-bloat-detector is a tiny command-line tool that shows you which dependencies are actually taking up the most space in your project. Instead of guessing from registry estimates, it walks your installed `node_modules`, measures the real on-disk bytes of every declared dependency (resolving pnpm an
spring-counter
spring-counter is a tiny, dependency-free React library that animates a number toward its target using a real spring simulation — mass, stiffness, and damping — instead of a fixed-duration tween, so stats count up and live values retarget with motion that actually feels physical. It ships a drop-in
react-render-cost
react-render-cost is a small command-line tool that ranks your React components by average render cost, reading the data your app already produces through React's built-in `<Profiler>`. Instead of scrubbing a flame graph, you get a ranked table: which components are actually expensive, how often the
headless-modal
headless-modal is an accessible, headless modal / dialog primitive for React — it owns the behavior that's easy to get wrong (focus trap, focus return, body scroll lock with scrollbar compensation, portal rendering, Escape and overlay-click dismissal, and the full WAI-ARIA dialog wiring) and ships z
headless-radio-group-react
headless-radio-group-react is an accessible, headless radio group primitive for React — it owns the tricky behavior (roving tabindex, orientation-aware arrow-key navigation, Home/End, Space/Enter, and the full WAI-ARIA radio pattern) and ships zero styling, so you keep complete control of the markup
magnet-cursor
magnet-cursor is a tiny React library for the "magnetic cursor" interaction you see on award-winning sites: a custom cursor that glides across the page and snaps onto your buttons and links as the pointer drifts near them. You render one component, tag the elements you want to feel sticky with `data
glow-card-react
glow-card-react is a tiny React library that adds a cursor-tracking glow to any card — a soft radial spotlight that follows the pointer and fades out when it leaves. It ships a drop-in `<GlowCard>` component and a headless `useGlowCard` hook, works with both React 18 and 19, and has zero runtime dep
I built a tool that grades how fragile your CSS is
css-unused-finder is a hosted, browser-only tool that reads any stylesheet and grades how fragile it is — flagging `!important` pileups, ID selectors, runaway specificity, deep descendant chains, magic z-index values and duplicate selectors, then rolling them into a 0–100 fragility score and an A–F
I built a CLI that prints a specificity heat map for your CSS
A tiny CLI that reads a stylesheet and prints a color-coded heat map of every selector's specificity — making the usually-invisible cause of failing CSS overrides visible at a glance.
typewriter-fx
typewriter-fx is a tiny, dependency-free React library for typewriter text effects with a cursor that actually behaves like a real one — solid while characters are landing, blinking only when the typing rests. It ships a drop-in `<Typewriter>` component for the common case and a headless `useTypewri
Gotham Garage
A personal-collection-first PWA for diecast collectors: scan a UPC or photo-match a loose car against your own library — so you never double-buy.
og-image-studio
OG Image Studio is a free, fully client-side editor for designing Open Graph / social-share images. You set a title and subtitle, pick a solid, gradient or image background, tweak fonts and colours, and watch a pixel-perfect 1200×630 card update live — then export it as a PNG in one click. Nothing i
kotomot
Translation management for devs — hosted API + Node, React Native, Flutter SDKs
bundle-cost-cli
CLI that prints bundle cost delta on every save
gradient-border-react
Animated gradient border that flows around any element
headless-toast
Tiny, fully-accessible toast primitive
scroll-reveal-kit
Drop-in IntersectionObserver reveal animations
Welcome to tech-brew
What this place is for: a weekly tech blog about the small libraries, tools, and platforms I build to stop writing the same code for the fifth time.