Build the Platform Core, Chat, and member integrations UI
Home, Chat, Settings and organization integrations use the shared navigation shell and real routes in the isolated Platform Next.js app. The browser and Sim Desktop share the renderer. A default-off server fixture supplies populated, empty and stress states without a database.
The shared App Router layout owns the sidebar. Selecting a chat, visiting Settings, or reopening the compact drawer preserves the reader’s position. Command K uses the shared menu rows and headings: Home, Settings and Integrations keep their icons, and workspace and chat results are text-only. Search, results and shortcut hints align to one inset, and moving from pointer to keyboard leaves only the active result highlighted.
Home and Chat share a reading column and a Recents component. Home opens recent websites in another tab; dismissal carries into Chat. The activity chart switches between Tasks run and Searches without losing its date range. Widgets and notifications share a height ceiling and scroll independently. Calendar’s Now control returns to the current day and time. Events open an external tab only when a provider supplies a URL; attendees have their own popover.
Navigation, tabs, recents and attachment previews share ControlRow. Invite recipients use compact address tags with an always-visible remove button inside each tag. Form dialogs focus the first available field and restore focus on close. Invite accepts typed and pasted addresses, supports keyboard removal and leaves sending to Phase 3. Chat keeps prose and tool activity aligned, and shares its time formatting and copy feedback with the rest of the Platform.
The member Integrations inventory uses workspace catalog descriptions for each provider. Its detail shows the provider name and description, then one connected credential with its actions menu. The inline connection prompt shares Home’s Email and Calendar styling and links to the Sim Search setup guide. Eligible tool approvals remain individual. Known OAuth permissions are grouped by purpose and always visible. Managed Search providers show their actual read-only operations, including Fireflies meeting search, transcripts, and summaries. The server fixture flag gates all sample connections. Member inventory and operation mapping.
See the component ownership map, Platform contract and Core/Chat source-state inventory. To run locally: SIM_PLATFORM_FIXTURES=1 bun run --cwd apps/sim dev:platform; visit /home?state=full, /chat/weekly-review?state=full /settings?state=full, or /integrations?state=full.
Verification exercises the production Next build, Chromium with fixture-on and fixture-off servers, and the native Electron renderer. Browser journeys measure scroll bounds, hit targets and spacing, exercise keyboard selection and focus return, and distinguish resting/hover/pressed feedback in both themes. The design audit checks ownership, token and variant use, timers, modal chrome and the fixture boundary. It recognizes JSX returned by local render helpers and active route fallbacks. The tracked Platform skill and contract route new work, cleanup and Settings reviews to the correct component library, and distinguish shared preferences from decisions owned by one feature.
Stacked on #9667, which targets staging.
Chat now steers instead of queueing. A message sent during a turn is applied to that turn at its next step, through the worker's durable v2 endpoint (simstudioai/mothership#929, which must deploy first; against an older worker a message waits for the turn's end and goes out as the next turn). If the turn ends without applying it, it goes out once as the next turn under the same id, and the worker refuses it if a run already applied it. The client queue is removed from every chat surface. Undelivered messages show a status line with Retry and Dismiss. Outgoing messages survive a reload through a per-tab journal, and anything past 10 minutes never sends itself. apps/sim/scripts/test-chat-steering-e2e.ts proves this across a real browser, app, worker and database (bun run test:chat-steering:e2e, not wired into CI).