New "Books" row in the Practice tab opens a library of bundled bilingual books. Each chapter renders Spanish paragraph-by-paragraph; tap any word for a definition sheet (DictionaryService with on-device AI fallback), or toggle the toolbar button to swap to the pre-computed English translation inline. Local-only Book + BookChapter SwiftData models added to the local container schema (reset version bumped to 5). DataLoader.seedBooks walks the bundle for `book_*.json` resources, so future books drop in without touching app code — just bundle a new JSON and bump bookDataVersion. First book: Olly Richards' "Spanish Short Stories For Beginners Vol 2" — 13 chapters, 2,646 paragraphs, bilingual. Scripts/books/ is the repeatable pipeline for future EPUBs: extract_epub.py → translate_chapters.py (per-chapter resumable jobs) → bundle_book.py. Translation is done by parallel Claude Code subagents reading per-job input files and writing output files — no API key required, matching the pattern used for the textbook vocab vision pass. See Scripts/books/README.md for the full how-to. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Books pipeline
Turns any EPUB into a chapter-structured JSON file the app bundles and reads.
TL;DR
cd Conjuga/Scripts/books
./run.sh /path/to/book.epub --slug my-book-slug
This runs Phase 1 (extract) and Phase 2 (manifest jobs), then stops and tells you how many translation jobs are pending. Run those via Claude Code subagents (Phase 2.5 below), then re-run ./run.sh to bundle the final file.
Phases
| Phase | Script | What it does | Output |
|---|---|---|---|
| 1 | extract_epub.py |
Unzip the EPUB, walk content.opf spine + toc.ncx navMap, group HTML files into chapters, strip HTML→text. |
build/<slug>/chapters.json |
| 2 | translate_chapters.py |
Split each chapter into ~30-paragraph translation batches. Each batch becomes a job with its own input/output file. Resumable: jobs whose output file already exists are skipped. | build/<slug>/jobs/<jobid>.input.json + _pending.txt |
| 2.5 | Claude Code subagents | Read each job's .input.json, translate Spanish→English, write <jobid>.output.json. See "Running translations" below. |
build/<slug>/jobs/<jobid>.output.json |
| 3 | bundle_book.py |
Merge chapters.json + every *.output.json into the final bundled JSON the app reads. |
Conjuga/Conjuga/book_<slug>.json |
run.sh chains 1 → 2 → 3. If Phase 2 produces pending jobs, Phase 3 still runs but bundles with empty paragraphsEN placeholders so you can preview app structure before translation completes. Re-running run.sh after subagents fill in the outputs gives you the real bundled file.
Adding a new book
-
Drop the EPUB anywhere on disk.
-
Run Phase 1+2:
cd Conjuga/Scripts/books ./run.sh /path/to/book.epub --slug my-bookSanity-check the chapter list it prints. If chapter grouping looks wrong (e.g. an EPUB without a usable
toc.ncx),extract_epub.pywill need a fallback heuristic — see "Open assumptions" below. -
Run translations (Phase 2.5). The default approach is to spawn Claude Code subagents from inside a Claude Code session pointed at this repo:
For each pending job ID listed in
build/<slug>/jobs/_pending.txt, hand a subagent the prompt atbuild/<slug>/jobs/_prompt_template.mdwith<JOB_INPUT_PATH>/<JOB_OUTPUT_PATH>filled in. The subagent reads the input, translates, and writes the output. Resumable — interrupted runs just leave the missing job IDs in_pending.txt.Cluster jobs into agent batches of ~5–10 jobs each to keep per-agent context manageable. ~5 parallel agents is a good throughput target.
-
Bundle:
./run.sh /path/to/book.epub --slug my-book # re-running pulls in the new outputs # or directly: python3 bundle_book.py my-book --require-all--require-allwill fail loudly if any job is still missing. -
Bump
bookDataVersioninDataLoader.swiftso the in-app store re-seeds the new book on next launch (or any time you re-run with new translations). -
Verify the file is bundled in
Conjuga.xcodeproj. The script writesbook_<slug>.jsonintoConjuga/Conjuga/Resources/; if that folder is part of a recursive group reference, Xcode picks it up automatically. Otherwise, add it manually or via thexcodeprojruby gem.
File layout
Conjuga/Scripts/books/
├── extract_epub.py # Phase 1
├── translate_chapters.py # Phase 2
├── bundle_book.py # Phase 3
├── run.sh # Orchestrator
└── build/ # gitignored
└── <slug>/
├── chapters.json
└── jobs/
├── _pending.txt
├── _prompt_template.md
├── ch01_b00.input.json
├── ch01_b00.output.json
└── ...
The final output (book_<slug>.json) lives at Conjuga/Conjuga/book_<slug>.json so the iOS app bundle includes it. (Existing textbook_data.json / conjuga_data.json use the same layout — files in the app target root rather than a Resources subgroup.)
Open assumptions
- TOC drives chapter boundaries. If an EPUB ships without a usable
toc.ncx, or the navMap is too granular (e.g. one navPoint per page),extract_epub.pywill need a fallback that groups by<h1>headings in spine order. - Spanish bold tags = inline emphasis. The Olly Richards books bold vocab hints inside paragraphs. We strip the bold and let the in-app dictionary lookup handle definitions instead. If a future book uses bold for something else (titles, etc.), revisit.
- Translation is per-paragraph 1:1. Subagents must preserve paragraph count and order.
bundle_book.pywill warn + pad/truncate if a job's output array length doesn't match its input — but that's a sign the subagent misbehaved.
Out of scope (intentional)
- OCR of vocab image tables (use
Scripts/textbook/if your book is image-heavy). - Exercise extraction (textbook pipeline).
- Pre-computed per-word annotations (the app uses
DictionaryService.lookup()at runtime). - Cover image extraction (covers are derived from a color hash in the app for now).