gistfile1.txt

// var packages = ['thumbd', 'underscore', 'request'];
var async = require('async');

function IssuePopulator(packages) {
  this.interval = 1000; // try to grab more packages every second.
  this.workSize = 10;
  this.packages = packages;
};

IssuePopulator.prototype.doWork = function() {
  var _this = this;
  
  console.log('doing a block of work.')

  if (this.packages.length) {
    // terminal condition.
    console.log('we finished grabbing all the packages.');
  } else {
    async.parallel(this.getWork(), function(err) {
      if (err) console.log(err);
      setTimeout(function() {
        _this.doWork();
      }, _this.interval);
    })
  }
};

IssuePopulator.prototype.getWork = function() {
  var _this = this,
    work = [];
  
  this.packages.splice(0, this.workSize).forEach(function(packageName) {
    work.push(
      function(done) {
       _this.getGitHubInfo(packageName, done);
      }  
    )
  });

  return work;
};

IssuePopulator.prototype.getGitHubInfo = function(packageName, done) {
  // do all the apis call you need to.
  // call done once all of them are done in sequenece().
  // you could use async.series, or you could use a bunch of closures.
};

// code elsewhere in your program loads `packages`.
(new IssuePopulator(packages)).doWork();