[mattetti]

We've been slowly migrating https://splice.com from Angular 1 to Angular 2, so far it's been great. We switched to TypeScript, we cleaned up our code organization. We are writing new components in ng2 and migrating old code we we go. The betas have been somewhat painful with bugs and breaking changes, but that's the price to pay. When it comes to performance and consistency, ng2 is a big winner. Why not React you might ask? React is great, but having to figure out/argue for each piece of the frontend stack isn't something we were willing to do. ng2 has its quarks bug at least it comes as a whole and that's super useful for us at this moment.

[wiradikusuma]

Re: switching to TypeScript, manual rewrite or transpilation? My codebase is CoffeeScript, so I'm also interested to hear if you have any experience with that (with Angular 2).

[admnor]

My advice would be to compile your CoffeeScript to JS, then start from there. That's assuming that CoffeeScript still produces readable, idiomatic JavaScript...?

As of TypeScript 1.8(?) you can set an "allowJs: true" flag in tsconfig.json, which tells TypeScript to include JS files in your build.

Then you can just manually add type annotations and ES2015/2016 goodness to your code and change the suffix to '.ts' on a file-by-file approach.

I'm doing this at the moment with a fairly large AngularJS 1.5 project, using Webpack with awesome-typescript-loader as the build system, and it's working perfectly so far.

[mattetti]

Progressive switch, we use TypeScript for new code and everything we touch old code, we try to convert from JS to TS. The tooling is amazing, even the skeptics in the team wouldn't go back to js now. Defining interfaces, using types really reduced the feedback loop and sped up our dev time. The one thing that is wish is that templates could verified by the compiler instead of waiting for runtime (react uses views written in code and therefore you get that for free when using react + TS)