Changelog

A running history of how BuffettKnowledge has evolved.

2026-05-21v2.0Major content push

Full-Text Expansion & Letter Intelligence

  • 1971–1976 Berkshire shareholder letters: full-text data entry complete (6 letters, ~73K words)
  • 1968–1970 partnership letters: full-text data entry complete (7 letters including dissolution notices)
  • Rich interpretation framework launched: Market Context, Key Numbers, Then vs Now comparisons per letter
  • Auto-linking in letter text: keywords now link to concepts, companies, and people inline
  • About page redesigned with FAQ section, stats sidebar, and FAQPage structured data for SEO
  • Changelog page upgraded with version sidebar navigation and archive highlights
2026-05-20v1.9Core feature fix

AI Q&A Reliability & Source Citations

  • AI Q&A API migrated from Gemini to OpenRouter (free tier, no credit card required)
  • Real search data integration: 82 letters, 49 concepts, 32 companies now powering AI retrieval
  • Clickable source tags added under every AI answer — jump directly to referenced letters, concepts, or companies
  • Typewriter effect race-condition bug fixed (infinite loading spinner resolved)
  • Empty sources bug fixed: hardcoded test data replaced with live dataset via prebuild script
  • AdSense sidebar placeholder added to AI Q&A page for future monetization
  • "New Chat" button visibility improved (solid green background)
2026-05-19v1.8

Partnership Letters Full-Text Data Entry (1965)

  • 1965 mid-year letter (Jul 9, 1965): fullText from 1965-1.docx — "First Half Performance", 10.4% vs 0.8% Dow (9.6pt advantage), Berkshire controlling interest acquisition discussed
  • 1965 special letter (Nov 1, 1965): fullText from 1965-2.docx — commitment letter for 1966, Ground Rule 7 introduced, Berkshire Hathaway valuation methodology explained
  • 1965 partnership letter (Jan 20, 1966): fullText from 1965-3.docx — "Our Performance in 1965", partnership gained 47.2% vs 14.2% Dow, widest margin in BPL history
2026-05-19v1.7

Partnership Letters Full-Text Data Entry (1963-1964)

  • 1963 mid-year letter (Jul 10, 1963): fullText from 1963-1.docx — Dempster Mill turnaround, 14% vs 10% Dow
  • 1963 partnership letter (Jan 18, 1964): fullText from 1963-3.docx — "Our Performance in 1963", 38.7% vs 20.7% Dow
  • 1963 special letter (Nov 6, 1963): fullText from 1963-2.docx — annual administrative letter to partners for 1964
  • 1964 mid-year letter (Jul 8, 1964): fullText from 1964-1.docx — plus 8.1% vs Dow plus 3.8% in first half
  • 1964 partnership letter (Jan 18, 1965): fullText from 1964-2.docx — "Our Performance in 1964", 27.8% vs 18.7% Dow
2026-05-19v1.6

Partnership Letters Full-Text Data Entry (1960-1962)

  • 1960 partnership letter (Jan 30, 1961): fullText populated from 1960.docx
  • 1961 mid-year letter (Jul 22, 1961): fullText populated from 1961.docx
  • 1961 partnership letter (Jan 24, 1962): fullText populated from 1961.docx
  • 1962 mid-year letter (Jul 6, 1962): fullText populated from 1962.docx
  • 1962 partnership letter corrected (Jan 18, 1963): replaced incorrect content from 1962-2.docx with correct text from 1962-3.docx
  • Automated .docx parsing pipeline: HTML table extraction, format preservation, letters.ts injection
2026-05-18v1.5

UI Polish & Cross-Reference Enhancement

  • TopBar navigation: upgraded to white background with border and scroll shadow for clearer visual separation
  • New "Links to This Page" sidebar module on every letter page — shows all concepts that reference the current letter
  • AdSense ad placements on letter detail pages: inline ad below title, sidebar ad at bottom
  • Full-site container width unified to max-w-7xl (1280px) across all 14 page types
  • Footer width fixed: max-w-content replaced with max-w-7xl, matching body container
  • About page: removed inner max-w-3xl constraint, full content width now used; text set to justify alignment
  • Blog link removed from sidebar navigation
2026-05-18v1.4

Branding & Navigation Refinement

  • Sidebar branding upgrade: "Buffett" in theme color, slogan "Built for value investors."
  • Favicon redesigned with lightbulb icon matching brand identity
  • Sidebar nav restructured: Home link added, Archive section renamed to Browse
  • AI Q&A moved from sidebar to top navigation bar (between Knowledge Graph and PDF Download)
  • New Changelog page added under About section
  • ShareToolbar added to every letter page with social sharing, copy link, print-to-PDF, and official source link
  • LetterInterpretation component: categorized Explore Further (Concepts / Companies / People)
2026-05-17v1.3

AI Q&A (RAG) + SEO Enhancements

  • AI Q&A feature launched with RAG architecture (retrieval-augmented generation)
  • Cloudflare Worker backend for OpenAI GPT-4o-mini integration
  • ChatWidget floating component + dedicated /ask page
  • JSON-LD structured data added across all pages (WebSite, Organization, Article, Person, etc.)
  • AdSense ad unit system integrated (header, sidebar, inline, footer placements)
  • Related Letters module added to company and person detail pages
  • Metadata numbers updated: 101 letters, 152 concepts, 71 companies, 17 people
  • public/ads.txt created for AdSense verification
2026-05-16v1.2

Knowledge Graph + Letter Interpretation

  • Interactive knowledge graph (Canvas force-directed graph, zero D3 dependency)
  • Homepage TOP ranking blocks: Top Concepts, Top Companies, Top People
  • Citation statistics engine (lib/citationStats.ts) for ranking by cited-in-letters count
  • Sidebar count badges on nav items showing real data totals
  • LetterInterpretation component: Overview, Key Takeaways, Sections, Explore Further
  • Warren Buffett added as a featured person in the database
  • All text justified with text-align: justify and hyphens: auto
2026-05-15v1.1

Data Expansion & Foundation

  • Letter count expanded from 68 to 101 total letters
  • Partnership letters (1956-1970): 37 letters added
  • Berkshire Hathaway letters (1971-2025): 62 letters added
  • Special letters (3): Buffett Partnership dissolution, 1999 Sun Valley, 2025 Farewell
  • Concept database expanded to 152 entries with cross-references
  • Company database expanded to 71 entries with investment timelines
  • People database: 17 key figures including Graham, Munger, Abel
2026-05-14v1.0

Initial Launch

  • BuffettKnowledge.com launched
  • Next.js 14 + TypeScript + Tailwind CSS stack
  • Letter archive with full-text search and year-based browsing
  • Concept tagging system with cross-reference tables
  • Company and people profiles with mention tracking
  • Random Buffett quote generator in top bar
  • PDF download hub for offline reading
  • Dark sidebar + warm parchment content area design system