static long stupidFib_collab(ICollab collab, int n) {
  int timeout = secondsToMS_int(10);
  
  new Var<Long> var;
  stupidFib_collab(collab, n, result -> {
    var.set(result);
    collab.done();
  });
  collab.run();
  ret waitForVarToBeNotNullWithTimeout(var, timeout);
}

svoid stupidFib_collab(ICollab collab, int n, IVF1<Long> continuation) {
  if (n < 3) ret with continuation.get(1L);
  
  new PairCollector<Long> collector;
  
  swap method collector.complete(a, b) {
    continuation.get(a+b);
  }
  
  collab.addWork(-> stupidFib_collab(collab, n-1, collector.setterForA()));
  collab.addWork(-> stupidFib_collab(collab, n-2, collector.setterForB()));
}