Coding Standards

Core Invariants

These rules are non-negotiable and must be preserved across all changes:

1. Terminal runtimes survive UI changes -- switching tabs, changing focus, or resizing layout must never restart a running PTY session
2. Single runtime owner -- RuntimeApplicationService is the sole owner of runtime lifecycle. All start/stop/replace/restart flows go through it
3. Port-adapter isolation -- application services depend on port traits (ports.rs), never on concrete Tauri or plugin imports
4. Domain purity -- domain crates depend on tabby-kernel only, never on tabby-contracts or each other
5. DTO boundary -- generated DTOs (tauri-bindings.ts) appear only in transport clients and snapshot-mappers, never in stores or components
6. Thin commands -- Tauri IPC handlers only deserialize, delegate, and return. No business logic
7. Projection-based publishing -- ProjectionPublisherPort accepts domain types, not DTOs. Infrastructure adapters handle mapping

TypeScript

• Strict mode enabled
• Prefer immutable patterns -- create new objects instead of mutating
• Functions under 50 lines, files under 800 lines
• No console.log in committed code
• No hardcoded values -- use constants or configuration

Rust

• Use tracing for diagnostics, not println!
• No .unwrap() or .expect() in production code
• Run cargo fmt and cargo clippy before committing
• Keep Tauri command handlers thin -- delegate to application services

Frontend Architecture

• Each feature owns its domain/, application/, and components/ directories
• Features do not import from other features' internals
• Zustand stores use internal read models derived from snapshots
• Shared UI components live in src/components/

Rust Architecture

• Domain crates are pure -- no framework dependencies
• Application services define behavior through port traits
• Infrastructure adapters implement ports and live in infrastructure/
• Cross-context coordination goes through AppShell, not direct service-to-service calls

Dependency Direction

Presentation -> Application -> Domain
                    |
              (port traits)
                    |
              Infrastructure

Never invert this direction. Domain code must not know about the presentation layer or infrastructure details.