Documentation Versioning: Strategies for Growing Products

As your product evolves, so must your documentation. But managing docs across multiple versions is one of the trickiest challenges documentation teams face. Here's how to get it right.

Why Documentation Versioning Matters#

When you release API v2, what happens to v1 documentation? If you:

• Delete it - You break existing integrations and frustrate developers
• Keep both without organization - You confuse developers about which to use
• Ignore it - You accumulate technical debt that becomes unmanageable

The solution is a thoughtful versioning strategy that serves both new and existing users.

Versioning Strategies#

1. URL-Based Versioning#

The most common approach: include the version in the URL.

https://docs.example.com/v1/authentication
https://docs.example.com/v2/authentication
https://docs.example.com/v3/authentication

Pros:

• Clear and explicit
• Easy to bookmark specific versions
• Search engines can index each version
• Simple to implement

Cons:

• Can fragment SEO authority
• Requires maintaining multiple complete doc sets
• Risk of version sprawl

Best for: APIs with breaking changes between versions, products with long support windows.

2. Dropdown Version Selector#

Keep a single URL structure with a version toggle:

https://docs.example.com/authentication
└── Version dropdown: [v3] [v2] [v1]

Pros:

• Single canonical URL per topic
• Consolidated SEO authority
• Clear current version while preserving access to old ones

Cons:

• More complex to implement
• Requires JavaScript for version switching
• Can confuse search engine indexing

Best for: Products with minor differences between versions, developer tools with frequent updates.

3. Inline Version Differences#

Show differences within the same page:

## Authentication
 
### v3 (Current)
Use bearer tokens for all requests:
\`\`\`bash
curl -H "Authorization: Bearer YOUR_TOKEN" ...
\`\`\`
 
### v2 (Deprecated)
Use API key in header:
\`\`\`bash
curl -H "X-API-Key: YOUR_KEY" ...
\`\`\`

Pros:

• Easy to compare versions
• Single page to maintain
• Good for migration guides

Cons:

• Pages become long and complex
• Not suitable for major differences
• Can overwhelm new users

Best for: Small differences between versions, configuration changes.

4. Branch-Based Documentation#

Use Git branches for each version:

main          → docs.example.com (latest)
release/v2.x  → v2.docs.example.com
release/v1.x  → v1.docs.example.com

Pros:

• Familiar workflow for developers
• Easy to backport fixes
• Complete isolation between versions
• Natural fit for open-source projects

Cons:

• Merge conflicts when backporting
• Can diverge significantly over time
• Requires multiple deployments

Best for: Open-source projects, products with long-term support versions.

Implementation Best Practices#

Default to Latest#

Always show the latest stable version by default. Developers who need older versions will know to look for them.

// Redirect bare URLs to latest version
if (path === '/docs/authentication') {
  redirect('/docs/v3/authentication');
}

Version Banner Warnings#

When viewing old documentation, warn users clearly:

<div class="version-warning">
  You're viewing documentation for v1 (deprecated).
  <a href="/docs/v3/authentication">View current version</a>
</div>

Maintain a Migration Guide#

For each major version, provide:

1. What changed - Breaking changes summary
2. Why it changed - Context for the decisions
3. How to migrate - Step-by-step instructions
4. Timeline - When old versions will be deprecated

## Migrating from v2 to v3
 
### Breaking Changes
 
| v2 | v3 | Migration |
|----|----| --------|
| `api_key` header | `Authorization: Bearer` | Update all API calls |
| `/users/list` | `/users` | Update endpoint URLs |
| Sync responses | Async with webhooks | Implement webhook handler |
 
### Step-by-Step Migration
 
1. Generate a new v3 API token in your dashboard
2. Update your SDK to version 3.x
3. Replace authentication headers...

Deprecation Timeline#

Communicate clearly when versions will be sunset:

## Version Support Policy
 
| Version | Status | End of Life |
|---------|--------|-------------|
| v3 | Current | - |
| v2 | Maintenance | December 2025 |
| v1 | Deprecated | March 2025 |
 
**Maintenance mode**: Security fixes only, no new features.
**Deprecated**: No updates, removal scheduled.

SEO Considerations#

Canonical URLs#

Point all version URLs to the latest as canonical (unless targeting specific version keywords):

<!-- On /v2/authentication -->
<link rel="canonical" href="https://docs.example.com/v3/authentication" />

Noindex Old Versions#

Consider noindexing deprecated versions to consolidate SEO:

<!-- On deprecated version pages -->
<meta name="robots" content="noindex, follow" />

Structured Data#

Include version information in your structured data:

{
  "@context": "https://schema.org",
  "@type": "TechArticle",
  "headline": "Authentication Guide",
  "version": "3.0",
  "dateModified": "2025-01-12"
}

Managing Documentation Debt#

Regular Audits#

Schedule quarterly reviews:

• Which versions are still actively used?
• What pages have the most confusion between versions?
• Are migration guides being followed?

Analytics by Version#

Track usage per version:

// Track which version users view
analytics.track('docs_viewed', {
  page: '/authentication',
  version: 'v2',
  source: 'search'
});

Use this data to:

• Prioritize migration outreach
• Identify stuck users
• Plan deprecation timelines

Automated Version Checks#

In your documentation build process:

# Example CI check
documentation-lint:
  rules:
    - no-broken-links
    - version-consistency
    - deprecated-warning-present
    - migration-guide-exists

Real-World Examples#

Stripe#

• URL versioning (/docs/api/2024-01-01)
• Changelog with every API version
• Automatic SDK version detection
• Clear upgrade paths

AWS#

• Service-specific versioning
• Version dropdown selector
• Long-term support for enterprise
• Detailed migration documentation

React#

• Branch-based versioning
• Version selector in navigation
• "Legacy" badge on old docs
• Codemods for automatic migration

Choosing Your Strategy#

Consider these factors:

Conclusion#

Documentation versioning isn't just about organizing files—it's about respecting your users' time and investment. A good versioning strategy:

1. Makes the current version obvious
2. Keeps old versions accessible
3. Provides clear migration paths
4. Communicates timelines transparently
5. Scales as your product grows

Start with the simplest approach that meets your needs, and evolve as your product matures.

Need versioned documentation without the headache? Dokly handles versioning automatically so you can focus on content.