systemjs: 'use strict' breaks importing

I’m just getting into ES6 modules, but I ran into an issue that surprised me. If I import a module using strict mode ('use strict';), the entire application fails.

index.js

var System = require('systemjs');

System.import('main').then(function(m) {
    console.log('loaded');
})

main.js

console.log('before import');

import { name } from './lib';
console.log('name: ' + name);

lib.js

'use strict'; // <-- Breaks app
export var name = 'Foo';

Running node index.js will silently finish without logging anything to stdout, but if I remove 'use strict'; from lib.js, I’ll get the expected output:

before import
name: Foo
loaded

Something else surprising is even if 'use strict;` is commented, the app still fails silently.

lib.js

// 'use strict';
export var name = 'Foo';