///|
/// A deterministic benchmark smoke program. It deliberately prints checksums
/// rather than elapsed time: CI proves the representative hot paths run, and
/// a benchmark harness can wrap this executable with its own timer/CPU setup.
fn scalar_update_checksum(iterations : Int) -> Double raise {
  let counter = @prometheus.Counter::new("benchmark_updates_total")
  let gauge = @prometheus.Gauge::new("benchmark_gauge")
  for index in 0.. Double raise {
  let descriptor = @prometheus.Descriptor::new(
    "benchmark_vector_total",
    CounterKind,
    variable_label_names=["worker", "outcome"],
  )
  let vector = @prometheus.CounterVec::new(descriptor, cardinality_limit=64)
  for index in 0.. Double raise {
  let registry = @prometheus.Registry::new()
  let histogram = @prometheus.Histogram::new(
    "benchmark_duration_seconds",
    [0.001, 0.01, 0.1, 1.0],
    unit="seconds",
  )
  registry.register_histogram(histogram)
  for index in 0.. 0.0005
      1 => 0.005
      2 => 0.05
      3 => 0.5
      _ => 5.0
    }
    histogram.observe(value)
  }
  let gathered = registry.gather()
  let sample = gathered.families[0].histogram_samples[0].value
  sample.count.to_double() + sample.sum
}

///|
fn encode_checksum(iterations : Int) -> Int raise {
  let descriptor = @prometheus.Descriptor::new(
    "benchmark_encoded_total",
    CounterKind,
    help="Benchmark exporter work",
    variable_label_names=["route"],
  )
  let vector = @prometheus.CounterVec::new(descriptor)
  for index in 0..