anchor.diff:  Sadly, this code will compile and run just fine, but it will not execute concurrently. To correctly implement concurrent
   operation, the following standard pattern is used:
   
  -.Example 2: Correct +Future+ concurrency:
  +.Example 4: Correct +Future+ concurrency:
   [source,scala,numbered]
   ----
   val f1 = read("1")
  
positive.code: +s_mach.concurrent+ adds an applicative workflow method for futures: +concurrently+. This method can more concisely
  express the pattern above:
  
  .Example 3: New +concurrently+ method
  [source,scala,numbered]
  ----
  for {
  
negative.code: 
  The same code, rewritten using +s_mach.concurrent+:
  
  .Example 2: Using +s_mach.concurrent+ to serially or concurrently transform and traverse collections:
  [source,scala,numbered]
  ----
  val oomItemIdBatch = (1 to 10).toList.map(_.toString).grouped(2).toList
  