--- title: Frontend & JS Digest — Week 26 date: Tue Jun 23 2026 16:00:00 GMT+0000 (Coordinated Universal Time) --- My favorite from this week is probably the MDN MCP server, because it solves a very real agent problem in the most boring useful way: give the model current browser facts instead of making it guess. But cssQuake is clearly the most fun link. ## Links ### News [Releasing Babel 8 today: ESM-only, drop ES5 default, and a smooth migration path](https://babeljs.io/blog/2026/06/16/8.0.0/) - Babel 8 is finally stable after eight years: ESM-only packages, built-in TypeScript types across Babel packages, Node 22+ support, and `@babel/preset-env` no longer targeting ES5/CommonJS by default. The migration is intentionally conservative, but the direction is clear: evergreen output unless you explicitly ask for legacy. [TanStack AI Beta: The Switzerland of AI Tooling Grows Up](https://tanstack.com/blog/tanstack-ai-beta) - TanStack AI reaches beta with a provider-agnostic, framework-agnostic API for text, structured streaming, tools, images, video, audio, realtime voice, middleware, MCP, AG-UI, devtools, and per-model TypeScript safety. The interesting bit is not another chat hook; it is the attempt to make AI app plumbing feel like normal TanStack infrastructure. [Wasp now lets you write your full-stack logic as a spec in TypeScript](https://wasp.sh/blog/2026/06/15/wasp-typescript-spec) - Wasp drops its custom spec DSL in favor of `*.wasp.ts` files built from `@wasp.sh/spec` constructors like `app`, `page`, `route`, `query`, `job`, and `api`. That means the high-level full-stack spec can use TypeScript composition, helpers, imports, filesystem reads, and feature-local organization while Wasp still generates the React, Node, and Prisma wiring. [Introducing the MDN MCP server](https://developer.mozilla.org/en-US/blog/introducing-mdn-mcp-server/) - MDN now has an experimental MCP server that exposes web docs and browser-compatibility data directly to agents and IDEs. This is exactly the sort of tool agents need: less training-cutoff folklore, more current platform facts when deciding whether `light-dark()`, Web Serial, or some new CSS/HTML feature is usable. [Announcing TypeScript 7.0 RC](https://devblogs.microsoft.com/typescript/announcing-typescript-7-0-rc/) - TypeScript 7.0 RC is the Go-based compiler release candidate: about 10x faster than TypeScript 6.0 in many cases, with parallel parsing/checking/emitting, `--checkers`, `--builders`, `--singleThreaded`, a rebuilt watch mode, LSP-based editor support, and the TypeScript 6 compatibility package for side-by-side migration. ### Article [Why we're bullish on loops](https://newsletter.posthog.com/p/why-were-bullish-on-loops?publication_id=1318225&post_id=202219171&isFreemail=true&r=3tqjnc&triedRedirect=true) - PostHog frames agentic work as loops: goal, context, evaluation, and an agent that can keep checking and steering itself. The examples are practical enough to matter: PR babysitters, bug fixers, flaky-test hunters, performance loops, and product-feedback loops that turn analytics into small shipped improvements. [The new HTTP QUERY method explained](https://kreya.app/blog/new-http-query-method-explained/) - A clear explainer for RFC 10008 and the new HTTP `QUERY` method: safe and idempotent like `GET`, but with a request body for complex read-only queries that do not fit nicely in URL parameters. The caveat is the practical one: client, proxy, server, cache, and bookmark support will lag for a while. [React Native, Hermes bytecode, and the Kindle homepage](https://sighery.com/posts/patching-kindle-homepage/) - Deep reverse-engineering writeup on Kindle's React Native homepage app, Hermes bytecode versioning, old Hermes builds, disassemblers, hbctool, and patching the homepage bundle. It is long, specific, and the kind of article that reminds you how much JavaScript infrastructure is now hiding inside "not web" devices. [React Performance: From Sluggish to Lightning](https://www.sethi.io/blog/react-performance-from-sluggish-to-lightning) - Practical React performance guide arguing that modern fixes are mostly structural: colocate state, use the children pattern, stop sprinkling `useMemo`/`useCallback`, let React Compiler handle the boring memoization, use transitions/deferred values for non-urgent work, split code, and profile before optimizing. [DrawDeck](https://www.inkandswitch.com/ink/notes/drawdeck/) - Ink & Switch design study for composable dynamic behavior using cards, piles, and little behavior tiles instead of conventional programming UI. The best part is the interaction model: users can disturb program state directly, and the system adapts around the intervention instead of pretending the process is sealed. [Refraction, dispersion, and other shader light effects](https://blog.maximeheckel.com/posts/refraction-dispersion-and-other-shader-light-effects/) - Maxime Heckel's shader walkthrough for real-time glassy light effects with React Three Fiber: FBO-based transparency, refraction, chromatic dispersion, chromatic aberration, specular highlights, and the math/glsl needed to make it feel physical rather than just like a filter. ### Library&tools [Introducing Nub: an all-in-one toolkit for Node.js](https://nubjs.com/blog/introducing-nub) - Nub is a Rust-powered command-line toolkit that embraces stock Node instead of replacing it: TypeScript/JSX/decorator execution through Oxc, `tsconfig` paths, `.env` loading, YAML/TOML imports, package/script/bin runners, watch mode, package installation, and Node version management in one binary. Very much the "what if Bun, but actually Node?" pitch. [zod-compiler](https://github.com/gajus/zod-compiler) - Build-time compiler for Zod schemas that keeps your existing schema code but turns validation into generated zero-overhead functions. The README claims 2-75x faster validation and support for Vite, webpack, esbuild, Rollup, and large projects with tens of thousands of schemas. Very attractive if runtime validation is on a hot path. [cssQuake](https://github.com/LayoutitStudio/cssQuake) - A port of Quake that renders BSP worlds as real HTML/CSS 3D geometry through PolyCSS, without WebGL or canvas. Original Quake data gets preprocessed into browser-ready JSON, image assets, and PolyCSS bundles, then the game runs in TypeScript. Completely unreasonable in the best possible way.