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Platform
Rule Evaluator
What happens per sample
Evaluation model
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Rule Evaluator
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Rule Evaluator

The Rule Evaluator is the hot loop of the runtime. For every sample on the local stream it runs the active rule pack supplied by the Rule Loader and, when a rule fires, hands the outcome to the Actuator Client.

Deterministic and bounded

Rules run inside a WASM sandbox with a strict per-evaluation time and memory budget. Evaluation is deterministic and bounded under ~10 ms so a single expensive rule can never stall the control loop.

What happens per sample

Evaluation model

  • Stateless and stateful rules are both supported: simple thresholds and windowed aggregates (e.g. “3 consecutive samples over limit”).
  • Window state lives in memory and is reset on rule-pack swap so a new pack starts from a clean, well-defined state.
  • Each fired outcome is tagged with the rule id and pack version for traceability.

Fail safe, not fail open

If a rule traps (timeout, sandbox fault) the evaluator drops that outcome and records a fault — it does not emit an unverified actuation. Safety-critical rules pair with a default-safe actuator state.