# funnel-core
> The pure workflow-DAG core of the nornir funnel — events, ids, state,
> topological readiness, history, the Plan-DAG projection, and the kanban-card
> board — with **no** warehouse / iceberg / model / GPU coupling.
Extracted from `nornir/src/funnel/` so both **nornir** (the viz funnel + Plan-DAG
panels) and **ordning-funnel** (idea → case graduation) share one idea→plan→node
DAG without dragging in nornir's storage stack. Everything here is deterministic:
given the same events + query string the output is bit-identical, so every surface
is golden-testable with no warehouse, no clock and no GPU.
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## The shape
A funnel is a fold of an append-only [`Event`] log into an in-memory [`Funnel`]:
```text
Event log ──apply──▶ Funnel ──┬─▶ history() → HistoryItem[] (intake list)
├─▶ cards_from_funnel() → Card[] → board() → Board (kanban)
├─▶ query_cards(q) → Card[] (YouTrack-style smart query)
├─▶ topo_ready() → NextStep[] ("what should I work on next?")
├─▶ simulate_flow() → FlowSim (time-step the DAG to done)
└─▶ PlanDag::from_funnel → PlanDag (nodes + edges + topo, viz)
```
Every projection is pure (`&Funnel → value`) and BTree-ordered, so the CLI, the
gRPC server and the viz all render the same bytes and never disagree.
## Benchmarks
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The board / smart-query projection (`cards_from_funnel` → `board` → `query_cards`)
and `PlanDag::from_funnel` are the hot paths the funnel UI runs on every render;
they are benched under `bench/` (`nornir bench run funnel-core`) and, for the
Plan-DAG assembly, by nornir's own `nornir.plan_dag_assemble` arm.
## Tests
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## Dependency graph
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## License
MIT OR Apache-2.0.