The Problem
Can’t afford regular lessons with tutors, and don’t have time for language schools. Built a system that learns my mistakes and strengths, trains with spaced repetition, tracks progress automatically, and picks daily topics.
Before / After
Before: A tutor twice a week → $240/month → go page by page through a textbook → no tracking of what exactly “falls apart”
After: Daily practice in Telegram → $4/month → AI notices I confuse “the subjunctive after expressions of emotion” → generates 20 targeted exercises exactly for that → finally mastered it
Bot base: 4 digitized textbooks (A1-B2 for Spanish/English), 2300+ exercises. 95% accuracy in detecting weak spots.
How It Works
Step 1: Telegram bot sends exercise from a digitized textbook.
Step 2: You answer. AI checks instantly. If there’s a mistake, it saves it with context (which rule, what type of error).
Step 3: After 10 mistakes on the subjunctive, AI sees a pattern and gives MORE practice exactly on that topic. Spaces drills over time (spaced repetition).
Result: Unlimited practice precisely on what is hard for you personally. When textbook tasks run out, AI generates new ones tailored to your weak spots.
Technical Architecture
- Content Digitization: OCR + manual proofreading of 4 full textbooks, YAML structure, 500+ units
- Triple Verification: Claude and GPT agree → correct; disagree → Opus for re-verification
- Error Tracking (Qdrant): Every mistake embedded and stored, similarity search surfaces related misses
- Adaptive Learning Engine: Calculates topic confidence (0-100%), assigns more practice to low-confidence topics
- Cost Optimization: GPT-4o-mini for simple checks, Claude for complex generation → ~$4/month
Real Numbers
- 4 textbooks digitized, 2300+ sub-exercises
- $4/month versus $240/month for a tutor
- 95%+ accuracy in detecting weak topics
- Only 73 out of 2300+ exercises required triple verification