---
model: openai/gpt-5.6-sol
service: opencode
timestamp: 2026-08-13T20:24:02Z
git_ref: 12b0d66e
diff_cmd: git diff HEAD~1..HEAD
---

The user asked to continue the paired piker broadcast-consumer work after
Tractor PR 490 stabilization. The next item was to stop cached feed callers
from mutating or consuming shared `Feed`/`Flume` quote-stream roots, then
review, verify and prepare a commit boundary.

> `git diff HEAD~1..HEAD -- piker/data/feed.py`

Changed `maybe_open_feed()` so the cached `Feed` exclusively owns provider
root streams and every caller, including the first cache owner, receives a
caller-local `Feed`/`Flume` view backed by one child subscription per provider.
The cache identity now includes normalized full symbol shape and stream policy.

Changed `Feed.open_multi_stream()` so every provider relay subscribes instead
of directly consuming a shared stream, and synchronizes relay startup before
yielding the merged channel. Each relay owns a cloned send channel so one
provider EOC cannot terminate its siblings. The module-level relay returns its
live child receiver through `TaskStatus` for typed retention and introspection.
Documented `Feed.pause()`/`Feed.resume()` as provider-context-wide controls
shared by local cache users.

> `git diff HEAD~1..HEAD -- tests/test_feed_broadcast.py`

Added real `Feed`, `Flume`, and Tractor broadcast regressions covering both
cache-miss owner and cache-hit paths, one-provider-many-market mapping,
multi-provider relay fan-out and startup, duplex controls, lexical child
closure, sibling survival after provider EOC, cached-root immutability, and
full cache-key differentiation.

Verification output:

```text
...                                                                      [100%]
3 passed in 0.02s

.                                                                        [100%]
1 passed in 0.01s
```

The second result is the existing EMS broadcast ownership regression. Ruff,
E501, compilation and whitespace checks passed. Repeated adversarial review
found and resolved shared `Feed.streams`, incomplete cache-key, fake-lifecycle,
relay-startup and first-owner asymmetry issues; final review reported no
findings.