# Feature Specification: Native WebKit Browser Backend

**Feature Branch**: `003-webkit2gtk-migration`  
**Created**: 2025-01-21  
**Status**: Draft  
**Input**: User description: "I want to ditch Wails and use Webkit2Gtk directly and create my own C go bindings"

## Execution Flow (main)
```
1. Parse user description from Input
   → If empty: ERROR "No feature description provided"
2. Extract key concepts from description
   → Identify: actors, actions, data, constraints
3. For each unclear aspect:
   → Mark with [NEEDS CLARIFICATION: specific question]
4. Fill User Scenarios & Testing section
   → If no clear user flow: ERROR "Cannot determine user scenarios"
5. Generate Functional Requirements
   → Each requirement must be testable
   → Mark ambiguous requirements
6. Identify Key Entities (if data involved)
7. Run Review Checklist
   → If any [NEEDS CLARIFICATION]: WARN "Spec has uncertainties"
   → If implementation details found: ERROR "Remove tech details"
8. Return: SUCCESS (spec ready for planning)
```

---

## ⚡ Quick Guidelines
- ✅ Focus on WHAT users need and WHY
- ❌ Avoid HOW to implement (no tech stack, APIs, code structure)
- 👥 Written for business stakeholders, not developers

### Section Requirements
- **Mandatory sections**: Must be completed for every feature
- **Optional sections**: Include only when relevant to the feature
- When a section doesn't apply, remove it entirely (don't leave as "N/A")

### For AI Generation
When creating this spec from a user prompt:
1. **Mark all ambiguities**: Use [NEEDS CLARIFICATION: specific question] for any assumption you'd need to make
2. **Don't guess**: If the prompt doesn't specify something (e.g., "login system" without auth method), mark it
3. **Think like a tester**: Every vague requirement should fail the "testable and unambiguous" checklist item
4. **Common underspecified areas**:
   - User types and permissions
   - Data retention/deletion policies  
   - Performance targets and scale
   - Error handling behaviors
   - Integration requirements
   - Security/compliance needs

---

## User Scenarios & Testing *(mandatory)*

### Primary User Story
As a developer/power user of the dumb browser application, I need the browser to have full control over its web rendering engine and browser capabilities without being limited by third-party frameworks, so that I can customize browser behavior, optimize performance, and maintain direct access to all native browser features.

### Acceptance Scenarios
1. **Given** the current browser uses a third-party framework, **When** I replace it with a native solution, **Then** the browser maintains all existing functionality (navigation, zoom, keyboard controls, history)
2. **Given** the native browser backend is implemented, **When** I want to add custom browser features, **Then** I can directly access and modify browser engine capabilities without framework limitations
3. **Given** the browser is running with the native backend, **When** users interact with web pages, **Then** performance is equal to or better than the previous framework-based implementation
4. **Given** the native backend is active, **When** the browser encounters different web content types, **Then** all standard web technologies render correctly

### Edge Cases
- What happens when the native bindings fail to load or initialize?
- How does the system handle web pages that stress-test browser engine capabilities?
- What occurs if the browser needs to interface with system-level features not exposed by the native bindings?

## Requirements *(mandatory)*

### Functional Requirements
- **FR-001**: System MUST render web pages with full HTML5, CSS3, and JavaScript support equivalent to modern browsers
- **FR-002**: System MUST maintain all existing browser controls (navigation, zoom, keyboard shortcuts) without regression
- **FR-003**: System MUST preserve existing user data (history, bookmarks, zoom settings) during migration
- **FR-004**: System MUST support the same web content types and media formats as the current implementation
- **FR-005**: System MUST provide identical or improved page loading performance compared to current framework
- **FR-006**: System MUST maintain cross-platform compatibility [NEEDS CLARIFICATION: which platforms need to be supported - Linux only, or multiple platforms?]
- **FR-007**: System MUST handle browser crashes gracefully without data loss
- **FR-008**: System MUST support developer tools and debugging capabilities for web content
- **FR-009**: System MUST maintain security features like sandboxing and content security policies
- **FR-010**: System MUST provide memory management equivalent to or better than current implementation

### Key Entities
- **Browser Engine Interface**: The abstraction layer that handles web content rendering, JavaScript execution, and browser feature access
- **Native Bindings**: The interface components that connect high-level application code with low-level browser engine capabilities
- **Migration State**: Configuration and data preservation mechanisms that ensure seamless transition from old to new backend

---

## Review & Acceptance Checklist
*GATE: Automated checks run during main() execution*

### Content Quality
- [ ] No implementation details (languages, frameworks, APIs)
- [ ] Focused on user value and business needs
- [ ] Written for non-technical stakeholders
- [ ] All mandatory sections completed

### Requirement Completeness
- [ ] No [NEEDS CLARIFICATION] markers remain
- [ ] Requirements are testable and unambiguous  
- [ ] Success criteria are measurable
- [ ] Scope is clearly bounded
- [ ] Dependencies and assumptions identified

---

## Execution Status
*Updated by main() during processing*

- [x] User description parsed
- [x] Key concepts extracted
- [x] Ambiguities marked
- [x] User scenarios defined
- [x] Requirements generated
- [x] Entities identified
- [ ] Review checklist passed

---