user { # User
  n1: circle label:"Start Parallel Execution"
  n5: rectangle label:"Record Parallel Execution outcome"
  n9: diamond label:"Monitor Parallel Execution status"
  n13: circle label:"End Parallel Execution"
  n1.handle(bottom) -> app.n2.handle(top)
  n1.handle(bottom) -> service.n3.handle(top)
  n1.handle(bottom) -> database.n4.handle(top)
  n1.handle(right) -> n5.handle(left)
  n1.handle(bottom) -> app.n6.handle(top)
  n1.handle(bottom) -> service.n7.handle(top)
  n1.handle(bottom) -> database.n8.handle(top)
  n1.handle(bottom) -> app.n10.handle(top)
  n1.handle(bottom) -> service.n11.handle(top)
  n1.handle(bottom) -> database.n12.handle(top)
  n5.handle(right) -> n13.handle(left)
  n9.handle(right) -> n13.handle(left)
  n1.handle(top) -> n9.handle(top)
}

app { # App
  n2: rectangle label:"Receive Parallel Execution event"
  n6: rectangle label:"Monitor Parallel Execution status"
  n10: rectangle label:"Monitor Parallel Execution status"
  n10.handle(right) -> user.n13.handle(bottom)
  n6.handle(right) -> user.n13.handle(bottom)
  n2.handle(right) -> user.n13.handle(bottom)
}

service { # Service
  n3: rectangle label:"Validate Parallel Execution conditions"
  n7: rectangle label:"Monitor Parallel Execution status"
  n11: rectangle label:"Monitor Parallel Execution status"
  n3.handle(right) -> user.n13.handle(bottom)
  n7.handle(right) -> user.n13.handle(bottom)
  n11.handle(right) -> user.n13.handle(bottom)
}

database { # Database
  n4: rectangle label:"Execute Parallel Execution action"
  n8: rectangle label:"Monitor Parallel Execution status"
  n12: rectangle label:"Monitor Parallel Execution status"
  n12.handle(right) -> user.n13.handle(bottom)
  n8.handle(right) -> user.n13.handle(bottom)
  n4.handle(right) -> user.n13.handle(bottom)
}