Architectural shift driven by user clarification: lazy-loading on first
use causes user-perceptible lag when the user-triggered action (e.g.
provider switch) propagates to a controller method that triggers the
first import. The fix is to pre-import heavy modules on a bg thread
at startup and have functions access them via _require_warmed().
Old design (rejected):
- from google import genai inside _send_gemini (lazy on first call)
- First user action that triggers this pays the cost; UI feels laggy
New design (this commit):
- Top-level heavy imports REMOVED from main-thread-reachable files
- AppController.__init__ submits warmup jobs to _io_pool (4 threads,
named 'controller-io-N')
- Each warmup worker imports its module and updates a thread-safe
warmup_status dict
- Functions access modules via _require_warmed(name), which assumes
the module is in sys.modules (warmed at startup)
- When all jobs complete, _warmup_done_event is set and registered
on_warmup_complete callbacks fire
- GUI shows status indicator + toast when warmup completes
- Hook API exposes /api/warmup_status and /api/warmup_wait
- Tests can call controller.wait_for_warmup() before exercising
warmup-dependent functionality
Phase 2 now bundles job pool + warmup (T2.3+T2.4 add warmup tests +
implementation). Phases 3-5 do 'remove top-level imports' instead of
'lazy-load'. Phase 7 is the notification surface (Hook API + GUI).
Definition of Done includes warmup-completion criteria, the
'no function-body imports' check, and an end-to-end 'provider switch
is INSTANT' smoke test.
No code changes; this is a planning update only.
Fulfills the existing backlog entry at conductor/tracks.md:152
(2026-06-05 root-cause analysis of live_gui wait_for_server timeouts).
Main Thread Purity Invariant: the main thread (entering immapp.run())
must never import a module heavier than imgui_bundle and the lean
gui_2 skeleton. Enforced by:
- static gate: scripts/audit_main_thread_imports.py (CI)
- runtime hook: tests/test_main_thread_purity.py (sys.addaudithook)
Threading constraint: no new threading.Thread(...) calls in src/.
All background work goes through AppController._io_pool
(ThreadPoolExecutor, max_workers=4, thread_name_prefix='controller-io').
9 phases, 57 tasks: audit+baseline, job pool, lazy-load SDKs, lazy-load
FastAPI, lazy-load feature-gated GUI, migrate ad-hoc threads, runtime
enforcement, hook API + diagnostics, verify+checkpoint.
Expected savings: ~2000-2400ms off main-thread import cost.
Target: import src.ai_client < 50ms (from ~1800ms), live_gui fixtures
no longer time out at wait_for_server(timeout=15).
- Restore monolithic architecture in gui_2.py to fix test compatibility.
- Implement full-width horizontal expansion for Markdown tables in discussion entries.
- Re-implement layered role-based tints using draw_list channels.
- Standardize Text Viewer docking ID to '###Text_Viewer_Unified'.
- Fix MiniMax compression routing and base URL.
- Fully restore missing theme_2.py definitions.
- Restore monolithic architecture in gui_2.py to fix test breakages and circular imports.
- Update Text Viewer stable ID to '###Text_Viewer_Unified' to definitively fix docking conflicts.
- Refactor discussion entry renderer to force full-width horizontal expansion for Markdown.
- Fully restore theme_2.py definitions (palettes, fonts, scale) while retaining role-tint logic.
- Robustify ImGui ID stack in imgui_scopes.py to prevent access violations.
- Verify all fixes with the comprehensive unit and visual test suite.
- Restore all rendering logic to gui_2.py to maintain monolithic architecture and test compatibility.
- Fix horizontal squashing of Markdown tables by ensuring full panel width in entry groups.
- Resolve Text Viewer docking conflicts by standardizing on a stable window ID ('###Text_Viewer_Unified').
- Fix theme initialization by restoring missing load/save functions in theme_2.py.
- Prevent ImGui access violations by ensuring ID stack always receives strings in imgui_scopes.py.
- Successfully verified all UI regressions with a passing unit test suite.
- Update Text Viewer window ID to '###Text_Viewer_Unified'.
- Ensures ImGui treats the window as a single stable entity across title changes.
- Prevents docking loop glitches.
- Insert imgui.new_line() before rendering discussion content.
- Ensures the Markdown renderer inherits the full horizontal width of the panel.
- Definitively fixes vertical squashing of tables and long text blocks.
- Resolve ImportError by correctly prefixing 'src' in modular renderers.
- Fix ImGui access violation by ensuring push_id always receives string IDs.
- Restore visible role-based background tints using layered rendering (channels).
- Definitively fix horizontal Markdown table widths by forcing group expansion.
- Centralize color management in theme_2.py and ui_shared.py.
- Standardize Files & Media inventory layout and remove legacy controls.
- Update test mocks to support modular UI and theme-driven styling.
- Display token metrics (input/output/cache) per response in Discussion Hub.
- Add total Discussion Token usage in the panel header.
- Implement 'Compress' feature to intelligently summarize and replace exhausted discussion histories using an AI subagent.
- Add _repair_minimax_history to close dangling tool calls from interrupted sessions.
- Add _trim_minimax_history to manage token limits and intelligently prune history.
- Integrate repair and trimming into _send_minimax loop.
- Resolves MiniMax error 2013 (tool call result does not follow tool call).
- Implement [Pure]/[Read] toggle for AI thinking monologues to allow text selection/copying.
- Fix TypeError: render_thinking_trace() missing 'entry_index' argument.
- Fix [+] buttons in Discussion and Comms history by correctly updating window state registry.
- Remove ListClipper from Discussion and Comms panels to fix variable-height clipping issues.
- Increase clipping heights for large entries to improve visibility.
- Fix code block scroll snapping in Markdown helper by robustifying text synchronization.
ed