step 1(b). cd nodejsdebug-boilerplate

What version of node are you using?

node version v6.9.1

I can't get it to work with v7.2.1.  I have another project that it works on for some reason.

I am unable to clone the example (Permission denied (publickey).). Is this module compiled and has source maps?

Weird. No source maps. It is just a single .js file.

const koa = require('koa');
const app = koa();
const server = app.listen(() => {
  console.log('opened server on', server.address().port);
});

I see the issue now, will investigate.

This is same issue as https://github.com/nodejs/node/issues/10338. Workaround would be to use "--inspect --debug-brk" or the recently added "--inspect-brk" flag. Please note that that bug is being looked at.

Script is retained through the reference to the callback function. Once the callback runs (and outputs the console message), the reference is cleared so the callback and all retained objects (including the script) get collected. By the time DevTools connect, VM has no knowledge about the script and cannot provide the script sources to the DevTools (by default, DevTools cannot read the local filesystem).