Hot code pushes

February 09, 2012 By Matt DeBergalis
Vote on Hacker News

Meteor 0.1.4 is out. The Meteor server now hot-pushes changes to JS, CSS, and HTML files to the browser, automatically, without making you reload the page. It's a leap forward for developer productivity.

Update your copy with meteor update, or quick start on OS X with curl install.meteor.com | sh.

Try this: inside your Meteor app (use examples/todos if you like), open up the CSS file and change a color. Any open browser will update to the new color, immediately, without a manual refresh. The same thing goes for changing a JavaScript file or HTML template. If you're like us, after ten minutes you'll wonder how you ever tolerated having to hit refresh all the time while developing an app.

In more detail, Meteor's reloading engine now pushes new client-side code and assets to each browser running your application. This is true while developing locally, in production when you deploy a new version with meteor deploy, and even when you restart a Meteor application bundle running on your own server. Your browser will save the contents of Session before the hot code push, so as long as you're using Collection and Session to hold client state, you'll be right back where you were.

This version of Meteor also includes under-the-cover changes to the live data protocol, but nothing user visible yet. Stay tuned for the next release.

The Meteor blog