very basic

performance.js

/*
      +------------+
      |     A      |
      +-[ ]----[ ]-+
         |      |
         |      V
         |    +------------+
         |    |     B      |
         |    +-[ ]--------+
         |       |
         V       V    <- - - - - - - - needs to synchronize here
      +------------+
      |     C      |
      +------------+

 Known:
  - Structure needs to be precomputed
  - Nodes emit promises (basically compiles a promise execution chain)
  
*/

// setup
var promise = require("node-promise"), sys = require("sys");
global.debug = function() { sys.puts(sys.inspect(arguments)); }

function A(out1, out2) {
  return function() {
    return function() {
      debug("A was called");
      var a = new promise.Promise();
 
      var p1 = out1(a);
      var p2 = out2; // a promise already
    
      promise.when(a, function() {
        debug("A fired when..");
        p1.resolve("new A1");
        p2.resolve("new A2");
      });
      setTimeout(a.resolve, 1000);
      return a;
    };
  };
}

function B(out1) {
  return function (in1) {
    debug("B was called");
    var _out1 = in1;
    var b = new promise.Promise();
    promise.when(in1, function() {
      debug("B fired when");
      b.resolve();
    });
    
    promise.when(b, function() {
      _out1.resolve();
    });
    
    return b;
  };
}

function C() {
  return function(in1, in2) {
    
    return function() {
      debug("C was called");
      var c = promise.all(in1,in2);
      promise.when(c, function () {
        debug("heh, C has completed");
      });
      return c;
    };
  };
}

// joins are special
var c = C();
var b = B(c);
var a = A(b,c);

debug(a(b,c(a,b))());