# v0.100.0: Unified transactional IVM execution

> **Status:** Planned
> **Scope:** Large
> **User promise:** *"A graph remains incremental when I refresh it manually or through a coordinator."*
> **Blocked by:** [v0.99.0](v0.99.0.md)
> **Source:** [September 2026 assessment](../plans/pg-trickle-assessment-and-pre-1.0-roadmap.md)

## Theme

Use one transactional refresh contract across scheduled, manual, external
graph, and lifecycle paths. Preserve the separate consistency contract for
IMMEDIATE mode. Replace the conservative Graph V1 rejection introduced in
v0.98.x with explicit experimental opt-in only after the common execution path
proves the required invariants. Stable admission remains closed until v0.104.0.

## Work

- Carry graph boundaries, owner identity, permitted strategies, cancellation
  policy, resource policy, and finalization duties in one scoped refresh
  context.
- Consolidate prepare, owner execution, apply, and finalization behavior across
  entry points.
- Remove the blanket manual FULL fallback for stream-table sources. Produce the
  downstream evidence needed for incremental composition in the common path.
- Enforce `full_policy` at each strategy decision, including runtime fallback.
- Restore backend-local state after every exceptional exit and keep graph
  refresh atomic.
- Define the consistency point for mixed FULL and differential graphs. Measure
  source-lock acquisition and hold time through the caller's transaction.

## Exit criteria

- [ ] A one-row INSERT, UPDATE, and DELETE in the checked-in three-node chain
      and four-node diamond fixtures reports `DIFFERENTIAL` for every populated
      downstream node.
- [ ] Scheduled, manual, and external paths agree on result multisets,
      effective strategy, frontiers, downstream changes, and rollback.
- [ ] `full_policy = 'ERROR'` rejects every whole-query FULL transition without
      forcing unsafe differential execution.
- [ ] No-data, initial population, reinitialization, and schema or function
      change paths finalize consistently.
- [ ] Tests cover graph failure followed by ordinary refresh in the same
      backend.
- [ ] Lock costs and caller-transaction duties are documented and measured.

## Scope control

Keep PostgreSQL as the executor. Do not add another scheduler or dataflow
runtime. Graph V1 remains experimental until v0.104.0 packages and passes its
independent conformance suite.