architecture

Architecture Skill

Determine correct file placement and structure for an Electron multi-process project.

Detailed References

• Renderer layer (components, hooks, utils, pages, CSS): references/renderer.md
• Main process & shared layer (bridges, services, worker, preload): references/process.md
• Project root & monorepo layout (directory structure, migration status): references/project-layout.md

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Decision Tree — Where Does New Code Go?

Is it UI (React components, hooks, pages)?
  └── YES → packages/desktop/src/renderer/              → see references/renderer.md

Is it an IPC handler responding to renderer calls?
  └── YES → packages/desktop/src/process/bridge/        → see references/process.md

Is it business logic running in the main process?
  └── YES → packages/desktop/src/process/services/      → see references/process.md

Is it an AI platform connection (API client, message protocol)?
  └── YES → packages/desktop/src/process/agent/<platform>/

Is it a background task that runs in a worker thread?
  └── YES → packages/desktop/src/process/worker/

Is it used by BOTH main and renderer processes?
  └── YES → packages/desktop/src/common/

Is it an HTTP/WebSocket endpoint?
  └── YES → packages/desktop/src/process/webserver/

Is it a plugin/extension resolver or loader?
  └── YES → packages/desktop/src/process/extensions/

Is it a messaging channel (Lark, DingTalk, Telegram)?
  └── YES → packages/desktop/src/process/channels/

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Process Boundary Rules

Hard rules — violating them causes runtime crashes.

Process	Can use	Cannot use
Main (packages/desktop/src/process/)	Node.js, Electron main APIs, fs, path, child_process	DOM APIs (document, window, React)
Renderer (packages/desktop/src/renderer/)	DOM APIs, React, browser APIs	Node.js APIs (fs, path), Electron main APIs
Worker (packages/desktop/src/process/worker/)	Node.js APIs	DOM APIs, Electron APIs
Preload (packages/desktop/src/preload/)	contextBridge, ipcRenderer	DOM manipulation, Node.js fs

Cross-process communication:

• Main ↔ Renderer: IPC via packages/desktop/src/preload/ + packages/desktop/src/process/bridge/*.ts
• Main ↔ Worker: fork protocol via packages/desktop/src/process/worker/WorkerProtocol.ts

// NEVER in renderer
import { something } from '@process/services/foo'; // crashes at runtime

// Use IPC instead
const result = await window.api.someMethod(); // goes through preload

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Naming Conventions

Directories

Scope	Convention	Reason
Renderer component/module dirs	PascalCase	React convention — dir name = component name
Everything else	lowercase	Node.js convention
Categorical dirs (everywhere)	lowercase	components/, hooks/, utils/, services/
Platform dirs (everywhere)	lowercase	acp/, codex/, gemini/ — cross-process consistency

Quick test: "Inside packages/desktop/src/renderer/ AND represents a specific component/feature (not a category)?" → PascalCase. Otherwise → lowercase.

Files

Content	Convention	Examples
React components, classes	PascalCase	SettingsModal.tsx, CronService.ts
Hooks	camelCase with use prefix	useTheme.ts, useCronJobs.ts
Utilities, helpers	camelCase	formatDate.ts, cronUtils.ts
Entry points	index.ts / index.tsx	Required for directory-based modules
Config, types, constants	camelCase	types.ts, constants.ts
Styles	kebab-case or Name.module.css	chat-layout.css

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Structural Rules

1. Directory size limit: Max 10 direct children. Split into subdirectories by responsibility when approaching.
2. No single-file directories: Merge into parent or related directory.
3. Single file vs directory: If a component needs a private sub-component or hook, convert to a directory with index.tsx.
4. Page-private first: Start code in pages/<PageName>/. Promote to shared only when a second consumer appears.

Test File Mapping

Tests mirror source files in tests/ subdirectories:

Source	Test
packages/desktop/src/process/services/CronService.ts	tests/unit/cronService.test.ts
packages/desktop/src/renderer/hooks/ui/useAutoScroll.ts	tests/unit/useAutoScroll.dom.test.ts
packages/desktop/src/process/extensions/ExtensionLoader.ts	tests/unit/extensions/extensionLoader.test.ts

When tests/unit/ exceeds 10 direct children, group into subdirectories matching source structure.

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Quick Checklist

• Code is in the correct process directory (no cross-process imports)
• Renderer code does not use Node.js APIs
• Main process code does not use DOM APIs
• New IPC channels are bridged through preload.ts
• Renderer component/module dirs use PascalCase; categorical dirs use lowercase
• Platform dirs use lowercase everywhere
• Directory-based modules have index.tsx / index.ts entry point
• Page-private code is under pages/<PageName>/, not in shared dirs
• No single-file directories
• No directory exceeds 10 direct children
• New source files are auto-included in coverage — verify they are not accidentally excluded in vitest.config.ts → coverage.exclude
• New services separate pure logic from IO