[teamleaderleo]

The native UI-layer host previously rendered a local copy of its chrome, so edits to real cmux NEXT SwiftUI modules could not appear in the host. This adds a Debug-only CmuxNextUiLayerPreview leaf product, reuses production CmuxNextDesign and CmuxNextIcons views, and maps the existing read-only projection into that surface. The checked-in vnode watcher follows the host and imported leaf-module roots, then terminates and restarts only the small host after a save; it never injects code into a running cmux app.

Before/after from the same fleet package harness:

• Before: 0 real CmuxNext SwiftUI modules linked by UiLayerHost; host view was copied chrome.
• After: 1 real preview leaf product linked (CmuxNextUiLayerPreview), with 3 production SwiftUI primitives (HairlineDivider, Icon, CmuxDialogActionButton) in the rendered path.
• Fleet compile: cmux-ci compile-check job 407fe2a93c491f3282666f42 passed CmuxNext at exact head aa4d74934c4 in 86 s (controller-selected worker; no worker was pinned).
• Warm capture slot on cmux-mac-mini-cua-5 at the host-seam predecessor: a one-line comment save in CmuxNextUiLayerPreview/UiLayerPreviewView.swift reached the first rendered frame in 1.653 s (ui-layer.reload to ui-layer.frame); a warm no-op swift build completed in 6.03 s. The host's read-only debug.window_record wrote 59 frames plus frames.json at 60 Hz without Screen Recording permission. The final socket-isolation/async-IO fix preserves this rendering path.

Full quality: p1-native-ui-layer.mp4

No capture: UiLayerHost is a standalone Debug SwiftPM executable; the packaged-app cmux-ci capture tour cannot launch this host, so the host-side recording above uses its own read-only debug.window_record socket.

Setup: docs/cmux-next/native-ui-host.md. Use CMUX_UI_LAYER_TRACE=1 to record ui-layer.reload and the first completed AppKit display pass (ui-layer.frame rendered_at_ns=...) in one stream. The preview product is off by default, excluded from CmuxNextApp and release app targets, and uses only read-only sample data or read-only attach methods.

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[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review aa4d749: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr24978 -f ref=p1-native-preview -f platform=macos -f backend_mode=local

red: cmux-next checks (god files, concurrency, crash safety, l10n); no finished base run on e835a3e to compare; do not merge until green; see lane-rules

Tour of aa4d74934c (run): no media. The tour job failed before the tour ran (build or setup); the run log has the output.

[teamleaderleo]

Bead cx-zhk0i created for this PR by the cmux coordinator.

[blacksmith-sh]

Found 12 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmp7i5ufsyy/summary-missing.json (live):/summary-missing.json (live):	View Logs
/tmp/tmpoldwo6av/summary-fail.json (live):/summary-fail.json (live):	View Logs
[new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows/ [new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows	View Logs
[new_workspaces] the window draws no frames/[new_workspaces] the window draws no frames	View Logs
[tabs] debug.tab_switch timed 0 of 40 switches/ [tabs] debug.tab_switch timed 0 of 40 switches	View Logs
[tabs] the window draws no frames/[tabs] the window draws no frames	View Logs
convention violations found (ERROR lines above)./ convention violations found (ERROR lines above).	View Logs
test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes (main.PreP ushGateTests.test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes)/ test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes (main.PreP ushGateTests.test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes)	View Logs
test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes (main.PreP ushGateTests.test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes)/ test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes (main.PreP ushGateTests.test_a_branch_that_merges_feat_cmux_next_in_is_judged_on_its_own_changes)	View Logs
test_a_merge_cannot_use_an_upstream_removal_to_pay_for_the_branch_s_own_debt (main. PrePushGateTests.test_a_merge_cannot_use_an_upstream_removal_to_pay_for_the_branch_s_ow n_debt)/ test_a_merge_cannot_use_an_upstream_removal_to_pay_for_the_branch_s_own_debt (main. PrePushGateTests.test_a_merge_cannot_use_an_upstream_removal_to_pay_for_the_branch_s_ow n_debt)	View Logs

...and 2 more test failures. View all on Blacksmith

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[github-actions]

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4014609062602 (b3efaad75c)
• cmux NEXT nightly 1.0.0-nightly.4014678890102 (e8697614f3)