Uint8Array toBase64 and toHex: Stop Round-Tripping Bytes Through btoa
JavaScript can finally turn bytes into base64 and hex (and back) without the String.fromCharCode and btoa dance. Here's how Uint8Array's new...
Sep 25, 2026
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4 min
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import defer: Lazy Modules Without Going Async
ES2026's import defer evaluates a module the first time you touch its namespace, not at startup, so you can move heavy work off the cold pat...
Sep 22, 2026
3 min
Turbopack's Persistent Build Cache Only Helps If Your CI Keeps It
Next.js 16.3 turned on Turbopack's persistent build cache by default and published numbers as high as 5.5x. Most CI pipelines will see exact...
Sep 21, 2026
4 min
CSS reading-flow: Fix the Tab Order Your Layout Broke
Grid and flexbox let you rearrange a layout without touching the DOM, which quietly breaks keyboard navigation. The reading-flow and reading...
Sep 19, 2026
3 min
WebNN: The Only Web API That Can Reach Your NPU
Almost every laptop shipped in the last two years has a neural processing unit sitting idle. WebNN is the only web standard that can actuall...
Sep 15, 2026
4 min
GraphQL @oneOf: Exactly One Input, Enforced by the Schema
OneOf Input Objects landed in the September 2025 GraphQL spec, which means the exactly-one-of-these-arguments rule you've been enforcing in ...
Sep 14, 2026
3 min
node --test: The Test Runner You Already Have Installed
Node's built-in test runner has been stable since v20 and now handles mocking, coverage, watch mode, and TypeScript files. Here's what it do...
Sep 12, 2026
3 min
Svelte Snippets: Reuse Markup Without a New Component
Snippets let you define reusable chunks of markup inline and render them like functions. They replace slots, kill the let: directive, and me...
Sep 8, 2026
3 min
CSS scroll-state() Queries: Styling Stuck, Snapped, and Scrollable
Sticky headers, snapped carousel slides, and scroll shadows have all been JavaScript jobs for a decade. Scroll-state container queries hand ...
Sep 7, 2026
3 min
Async Svelte: Using await Directly in Your Components
Svelte 5.36 lets you use await at the top level of a component, inside $derived, and in your markup. Here is how synchronized updates, bound...
Aug 31, 2026
4 min
The Web Locks API: One Tab Does the Work, the Rest Wait
Your app already runs in five tabs at once, and they all think they are in charge. The Web Locks API gives the browser a real mutex so only ...
Aug 29, 2026
4 min
Form-Associated Custom Elements: Web Components That Belong in a Form
Custom elements can be real form controls. Here is how formAssociated, ElementInternals, and setValidity retire the hidden-input hack for go...
Aug 29, 2026
3 min
Next.js Partial Prefetching: One Shell Per Route, Not One Per Link
Next.js 16.3 stops firing a prefetch request for every link in the viewport and caches one reusable loading shell per route instead. Here's ...
Aug 24, 2026
4 min
Declarative Partial Updates: Out-of-Order HTML Streaming Without a Framework
Chrome 148 ships experimental support for filling HTML placeholders out of order and streaming markup into the DOM. Here's how the new templ...
Aug 22, 2026
3 min
React's Activity Component: Hide UI Without Losing Its State
React 19.2's Activity component hides a subtree instead of unmounting it, so state, scroll position, and DOM survive the round trip. Here's ...
Aug 18, 2026
3 min
revalidateTag vs updateTag: Next.js Split Cache Invalidation in Two
Next.js 16 gave cache invalidation two different functions instead of one, and the split maps to a real distinction: content that can lag ve...
Aug 17, 2026
3 min
CSS text-box-trim: The End of Fudging Vertical Padding
Buttons that look bottom-heavy at padding: 12px aren't your fault, they're half-leading. text-box-trim finally lets CSS cut that invisible s...
Aug 14, 2026
3 min
Trusted Types Is Baseline: DOM XSS Is Now a Type Error
Firefox 148 shipped Trusted Types in February 2026, making it Baseline. Here's how to turn every dangerous innerHTML assignment in your app ...
Aug 11, 2026
3 min
The Long Animation Frames API: Find What Actually Broke Your INP
Your field data says INP is 400ms. Your local profile says everything is fine. The Long Animation Frames API closes that gap by naming the s...
Aug 10, 2026
3 min