I built a Rust CLI that takes an EPUB and rewrites it at a target CEFR level (A1–C2) using an LLM. Give it a German novel and ask for Portuguese at A2 — it produces a new EPUB ready for your Kindle.

For beginner levels (A1/A2), it runs a two-pass pipeline: first simplify in the source language, then translate. This produced 15–25% better vocabulary coverage than doing both in one shot.

It uses Groq or Ollama (local) as backends. A sample book (Kafka's Metamorphosis) is included so you can try it immediately.