Syntopica

Overview

Syntopica is an AI-powered reading companion named after syntopical reading — the highest level of reading described by Mortimer Adler in How to Read a Book: reading multiple books on a single subject and constructing an analysis that none of them contain individually.

The Capture layer is complete: a Chrome extension imports your full Amazon library (Kindle, Audible, physical) and Kindle highlights with zero manual entry, using Amazon's GraphQL API for books and DOM scraping for highlights. Background sync keeps everything current on a 4-hour cycle. The web app provides a library grid with covers, book detail pages, and a highlights viewer.

A three-source metadata enrichment pipeline (Google Books → OpenLibrary → Wikidata SPARQL) achieves 93% description coverage and 92% ISBN coverage. The Think layer is live: AI-powered collections for grouping books by theme, asking questions across them, and generating citation-backed synthesis.

Why we built it

Serious readers accumulate thousands of highlights across hundreds of books, but those ideas stay siloed. Goodreads tracks what you've read; Readwise resurfaces quotes. Neither helps you think across books. Syntopica is built for the reader who wants to ask "What do these five authors say about attention?" and get a cited, synthesized answer drawn from their own library.

How it works

1. Install the Chrome extension — it reads your Amazon library and Kindle highlights automatically 2. Import — Books arrive in chunked uploads (150/chunk), highlights in batches of 300, with auto-retry and recovery 3. Enrich — A background worker progressively enriches books from Google Books, OpenLibrary, and Wikidata SPARQL 4. Browse — Library grid, book detail pages, all-highlights view with search and filtering 5. Synthesize — AI collections for cross-book questions, citation-backed synthesis, and single-book deep reading assists

Feature highlights

• Full Amazon Library Import — Kindle, Audible, and physical books via Chrome extension; 4,200+ books imported at scale with zero errors
• Kindle Highlight Extraction — 29,000+ highlights imported via DOM scraping with multi-pass scroll strategy
• Background Auto-Sync — 4-hour cycle keeps library and highlights current
• Three-Source Enrichment — Google Books + OpenLibrary + Wikidata SPARQL for 93% description coverage
• Library Grid + Book Detail — Cover images, metadata, highlights viewer, search and filters
• Cross-Book Synthesis — AI collections, thematic grouping, citation-backed analysis

Notes

• Tech Stack: Next.js 16, TypeScript, React 19, Tailwind CSS 4, Neon PostgreSQL + Drizzle ORM, Supabase Auth, OpenAI (GPT-5.4 / GPT-5.6 class models + text-embedding-3-small + Whisper), Chrome Extension (Manifest V3), Sentry, Amplitude
• Chrome Extension: live on the Chrome Web Store — https://chromewebstore.google.com/detail/gppcjaalakkmokmjoaljckfblibkmmcp
• Current Status: Live beta — Capture and Think both complete. Cross-library synthesis via collections, syntopical briefs, and single-book deep reading are live; citations link to the reader's own highlights.
• For Whom: Serious readers, researchers, lifelong learners who want their reading to compound