Source-Driven Development

Every framework-specific code decision must be backed by official documentation. Don't implement from memory.

When to Use

• The user wants code that follows current best practices for a given framework
• Building boilerplate, starter code, or patterns that will be copied
• Implementing features where the framework's recommended approach matters
• Any time you are about to write framework-specific code from memory

The Process

DETECT ──→ FETCH ──→ IMPLEMENT ──→ CITE
  │          │           │            │
  ▼          ▼           ▼            ▼
 What       Get the    Follow the   Show your
 stack?     relevant   documented   sources
            docs       patterns

Step 1: Detect Stack and Versions

STACK DETECTED:
- React 19.1.0 (from package.json)
- Vite 6.2.0
- Tailwind CSS 4.0.3
→ Fetching official docs for the relevant patterns.

Step 2: Fetch Official Documentation

Source hierarchy:

Priority	Source	Example
1	Official documentation	react.dev, docs.djangoproject.com
2	Official blog / changelog	react.dev/blog
3	Web standards references	MDN, web.dev
4	Browser/runtime compatibility	caniuse.com

Not authoritative — never cite:

• Stack Overflow answers
• Blog posts or tutorials
• AI-generated documentation
• Your own training data

Step 3: Implement Following Documented Patterns

Write code that matches what the documentation shows.

When docs conflict with existing code:

CONFLICT DETECTED:
The existing codebase uses useState for form loading state,
but React 19 docs recommend useActionState for this pattern.
(Source: react.dev/reference/react/useActionState)

Options:
A) Use the modern pattern (useActionState)
B) Match existing code (useState)
→ Which approach do you prefer?

Step 4: Cite Your Sources

Every framework-specific pattern gets a citation:

// React 19 form handling with useActionState
// Source: https://react.dev/reference/react/useActionState#usage
const [state, formAction, isPending] = useActionState(submitOrder, initialState);

Citation rules:

• Full URLs, not shortened
• Quote relevant passages for non-obvious decisions
• If you cannot find documentation, say so explicitly:

UNVERIFIED: I could not find official documentation for this
pattern. This is based on training data and may be outdated.
Verify before using in production.

Verification

After implementing with source-driven development:

• Framework and library versions were identified from the dependency file
• Official documentation was fetched for framework-specific patterns
• All sources are official documentation
• Code follows the patterns shown in the current version's documentation
• Non-trivial decisions include source citations with full URLs
• No deprecated APIs are used
• Conflicts between docs and existing code were surfaced
• Anything unverified is explicitly flagged