Meteor.js

Migrating a Blaze app to Meteor 3 with Rspack? Your client/main.js becomes the explicit import tree for your entire client. Forget to import a .html template? {{> myTemplate}} silently renders nothing. Forget a .js file? Its helpers and event handlers simply don't exist. No error. Every Blaze template, every helpers file, every collections file — has to be imported from your entry point. // client/main.js import './main.import.less'; import './views/application/layout.html'; import './views/posts/show.html'; import './views/posts/show.js'; import '../lib/router.js'; // ...every single one Start with the layout, work outward. When something's missing, Blaze logs Template.X is not defined.

Worst kind of bug when migrating Iron Router to Meteor 3: the kind that produces zero errors. Iron Router auto-discovers controllers by naming convention. A route called postsShow looks for a global called PostsShowController. In Meteor 2, top-level assignments were file-scoped globals. It worked. In Meteor 3, const PostsShowController = ... is module-scoped. Iron Router can't find it. But the route still renders. Page loads. No console errors. Subscriptions never fire. Database has thousands of docs, Minimongo shows zero. The fix: stop relying on naming convention. Pass the controller explicitly. this.route('postsShow', { path: '/posts/:slug', controller: PostsShowController, }); Do this for every route with a controller in Meteor 3.

Subtle Meteor 3 gotcha that can cost you hours: On the server, always use the Async methods: - findOneAsync - updateAsync - fetchAsync On the client, keep using sync findOne() inside Blaze helpers and Tracker.autorun. Why: findOneAsync returns a Promise. Tracker can't track Promises. Your helper stops being reactive. Symptom: page loads fine on first render, but when new data arrives from a publication, the view never updates. No errors. No warnings. Just silently stale UI. The sync minimongo methods are deprecated but still functional, and they're the only way to get Tracker reactivity. Server = always async. Client = sync when you need reactivity.

Migrating a Meteor 2 app to 3.x? Search your codebase for this pattern: ^[A-Z]\w+ = (capital letter at the start of a line, no const/let/var) In old Meteor, this created a file-scoped global visible everywhere: PostsController = RouteController.extend({ ... }) Meteor 3 enforces strict mode. Every one of those becomes ReferenceError: X is not defined at runtime. The fix is mechanical but has to be deliberate: - Used only in this file? Add const - Shared across files? export it, then import where needed We found ~15 of these in a real production migration. Each one only surfaced when the app crashed on startup. Find them proactively before the runtime does.

This week I’ve updated “flow-router” a core routing library of @meteorjs apps. Now library ships with Agent SKILLS.md! Simplifying Meteor.js development in the age of AI #webdev #oss #javascript

Meteor apps behave differently in production. DDP connections instead of stateless HTTP. Long-lived subscriptions can leak memory. Reactive recomputations that spike CPU out of nowhere. Client and server state that drifts silently. A new community guide covers how to actually monitor all of this: what to watch at the system, application, and user-impact layers, plus how to set up Monti APM, Sentry, and Uptime Robot in a Meteor project. Worth reading if you ship Meteor to production 👇 blog.galaxycloud.app/monitoring-and…

Monitoring a Meteor app isn't like monitoring a typical Node backend. DDP connections are persistent. Subscriptions fail silently. Memory grows from long-lived sessions. CPU spikes during reactive recomputations. Your APIs can look fine while users are disconnected.

@hrgooo timing is everything

@meteorjs These tweets are so on point

Meteor 3.4.1 is out! A community-driven patch with 25+ contributors, a critical DDP fix for production apps, and a more polished Rspack experience. Here's what's new ↓

Before deploying to @CloudByGalaxy, check that `.meteor/release` is committed. It defines the Meteor version used in production. Without it in sync, local and production can run different versions. Then comes the bug that "only happens in prod".

Plus: • Faster meteor test --full-app runs • Node v22.22.1 • Dozens of smaller fixes and improvements across the core Upgrade with: meteor update --release 3.4.1 ☄️

Starting a new Meteor app got better too: • meteor create now fetches examples dynamically • New --from-branch and --from-dir flags (clone from any branch or directory of any Git repo) • New TypeScript + Tailwind skeleton out of the box

A single API request rarely hits MongoDB once. It hits it 5, 10, sometimes 20 times. At 80ms per call, the issue isn't your database: it's the network distance. 10 MongoDB calls × 80ms = a slow app, no matter how clean your code is.

Official announcement: rspack.rs/blog/announcin…

So, @rspack_dev 2.0 was launched a few weeks ago and Meteor is on the official ecosystem list 🎉 The big win for large Meteor apps: persistent cache now drops memory usage by 20%+, and SWC minimizer cache hits make builds ~50% faster. Less RAM, faster builds. We'll take it 🤝

@meteorjs 3.4.1 is out! Rspack consolidation, revitalized examples, and important fixes. I've also contributed with a new skeleton (starter) for TypeScript and Tailwind. A popular combination in the wider JS ecosystem! blog.galaxycloud.app/meteor-3-4-1-i…

The most underrated file in a Meteor app: `.meteor/release`. It defines the exact framework version your app uses. Commit it? Local, CI, and production stay in sync. Skip it? Good luck debugging bugs that only happen in one environment.

🚀 @meteorjs 3.4.1 is out: Rspack consolidation, revitalized examples, and a DDP session memory leak fix that matters for production apps. The framework Galaxy is built around keeps shipping. Check it out: blog.galaxycloud.app/meteor-3-4-1-i…