# Batch 90 Report — AZ-619 Phase A: build_pre_constructed seeds c13_fdr + clock (cycle 1)

**Batch**: 90
**Date**: 2026-05-19
**Context**: Product implementation (greenfield Step 7 — Implement; AZ-618 umbrella, Phase A of 6)
**Tasks**: AZ-619 (2 cp) — 1 task
**Cycle**: 1
**Verdict**: COMPLETE — PASS (committed as `8abfb02`)
**Note**: Report backfilled retroactively — the prior session committed code, transitioned tracker, and archived the spec but did not write this report. Content reconstructed from the commit (`git show 8abfb02`), the task spec in `_docs/02_tasks/done/AZ-619_pre_constructed_phase_a_c13_fdr_clock.md`, and the prior `_docs/_autodev_state.md` `sub_step.detail`.

## Summary

First of six subtasks decomposing the AZ-618 umbrella ("airborne_bootstrap pre-constructed dict"). Phase A introduces the public entry-point `build_pre_constructed(config) -> dict[str, Any]` and seeds the two foundational keys (`c13_fdr`, `clock`). Phases B..F (AZ-620..AZ-624) extend this function additively without breaking the AZ-619 contract.

### AZ-619 — build_pre_constructed Phase A (2 cp)

* **`src/gps_denied_onboard/runtime_root/airborne_bootstrap.py`** — new public `build_pre_constructed(config)` plus two internal builders:
  * `_build_c13_fdr(config) -> FdrClient` via `make_fdr_client("airborne_main", config)`. Per-producer cache makes the instance identity-stable across calls (AC-619.2).
  * `_build_clock(config) -> WallClock`. Replay-mode override is not done here — `compose_root` merges `replay_components` over `pre_constructed`, replacing `WallClock` with `TlogDerivedClock` in replay binaries (existing contract).
* **New module constant** `AIRBORNE_MAIN_PRODUCER_ID = "airborne_main"` for the producer ID used by the bootstrap FdrClient.
* **`__all__`** updated to export `build_pre_constructed`.

## Out of scope (deferred)

* All other 10 keys in `AIRBORNE_REQUIRED_PRE_CONSTRUCTED_KEYS` — AZ-620 (c6 storage), AZ-621 (c7 inference), AZ-622 (c3 runtimes), AZ-623 (RANSAC + c5 helpers).
* `runtime_root.main()` integration + full AC-1..AC-5 umbrella verification — AZ-624.
* Mandatory-Tier-2 Jetson run — consolidated at AZ-624 to avoid 6 separate Jetson runs for one feature (per `_docs/02_document/tests/tier2-jetson-testing.md`).

## Test Results

* New unit tests: **5** under `tests/unit/runtime_root/test_az619_pre_constructed_phase_a.py` covering AC-619.1 (required minimum keys present with correct types) and AC-619.2 (`c13_fdr` identity stability across calls).
* Combined run with AZ-591 regression: **12/12 passed** (no regression in the registry seam).
* No new linter errors introduced.

## File Ownership

* OWNED (component `runtime_root`):
  * `src/gps_denied_onboard/runtime_root/airborne_bootstrap.py`
  * `tests/unit/runtime_root/test_az619_pre_constructed_phase_a.py`
* READ-ONLY: `runtime_root` imports from `fdr_client` (`make_fdr_client`) and `clock` (`WallClock`) Public APIs only.
* No FORBIDDEN-zone writes.

## State

* Spec moved: `_docs/02_tasks/todo/AZ-619_pre_constructed_phase_a_c13_fdr_clock.md` → `_docs/02_tasks/done/`.
* Commit: `8abfb02 [AZ-619] Phase A: build_pre_constructed seeds c13_fdr + clock`.
* Tracker: AZ-619 transitioned to **In Testing**.
* `_docs/_autodev_state.md` advanced to `last_completed_batch: 90`.

## Next Batch

* **Batch 91**: AZ-620 (3 cp) — Phase B of AZ-618 umbrella. Adds `c6_descriptor_index` (DescriptorIndex) and `c6_tile_store` (TileStore) keys to `build_pre_constructed`, plus an `AirborneBootstrapError` path when a BUILD-flag mismatch leaves a consuming component without its dependency.