New idea

[lastmjs]

We're getting close to es modules being supported in all major browsers. Once we drop support for SystemJS, we're going to have some issues. How do we know which files to transpile? How do we import .ts files if .ts extensions aren't allowed? A simple way to fix this is to allow .js files to contain ts. Perhaps put a simple directive at the top indicating the file should be transpiled. Then all files could be imported the same way, and only the files you indicate will be transpiled.

[lastmjs]

Once the atom-typescript plugin allows .js files to have TS code inside, this should work awesomely...I really like this idea, just put a directive at the top. Then everything is JS...if you want TS, just put TS in your JS. Then everything will work as expected.

[lastmjs]

Just transpiling all JS or TS files might work