Define category-specific subcategories #386

Context

In the 12 Feb meeting, the team agreed that the main catalogue navigation should use category-specific subcategories (unique to each top-level category) rather than cross-cutting topics that repeat across categories. Paula made a strong UX case that duplicating subcategories across parent categories is confusing for users and violates standard information architecture principles.

Cross-cutting topics (e.g. AI Lifecycle, Sustainability Metrics) will still exist but as tags for filtering and alternative browsing — not as navigation items.

What needs to happen

• For each top-level category that has a long pattern list (Architecture has 14+), propose 2–3 unique subcategories that meaningfully reduce the list for scanning
• Follow the rule of thumb: only create a subcategory if it would contain 3+ patterns; categories with ≤7–9 patterns can remain flat
• Document the proposed subcategories in the patterns spreadsheet for team review
• Confirm with the team that the cross-cutting topics list is complete and suitable for use as tags

Acceptance criteria

• Every top-level category with >7 patterns has proposed subcategories
• No subcategory name appears under more than one parent category
• Cross-cutting topics are documented separately as the tag taxonomy
• Team consensus reached via async review or next meeting

References

• Meeting decision: Subcategorization approach agreed 12 Feb 2026
• Related: Homepage will offer multiple browse routes (by category, by persona, by tag)