gistfile1.js

if (Meteor.isClient) {
  Meteor.subscribeReactive = function(name) {
    // ...
  };
}

var relations = {};
Meteor.Collection.prototype.relations = function(relations) {
  relations[this._name] = relations;
};



if (Meteor.isServer) {
  Cursor = Object.getPrototypeOf(new Meteor.Collection('_void').find()).constructor;

  Cursor.prototype.join = function(name) {
    this._joins = name;
    return this;
  };
  
  Cursor.prototype.connection = function() {
    return this;
  };

  var getCollection = function(name) {
    for (var object in global)
      if (global[object] instanceof Meteor.Collection)
        if (global[object]._name === name)
          return global[object];
  };

  Meteor.publishReactive = function(name, fn) {
    var cursor = fn();

    var collectionName = cursor._cursorDescription.collectionName;
    // var collection = getCollection(cursor._cursorDescription.collectionName);
    console.log(cursor._joins);

    Meteor.publish(name + '_' + cursor._joins, function(key) {
      return relations[collectionName][cursor._joins];
    });
  };
}