Lotty — AI Language Tutor

A full-stack language-learning web app — designed, built, and deployed end-to-end, solo.

What it is

A platform for learning foreign languages through personal vocabulary training, spaced repetition, and AI-generated content (stories, conversation practice), rather than a fixed course structure.

My role

Owned the product across the full stack — from UI/UX design and database architecture to frontend implementation, AI integration, and the production deployment pipeline.

Skills demonstrated

Frontend development — Vue 3, internationalization (i18n, 6 languages)
Backend development — REST API design, PostgreSQL data modeling, authentication
UI/UX design — designed the interface and interaction patterns from scratch, including a shared component library (ui-kit) and mobile-friendly responsive layouts
AI integration — working with multiple LLM/speech providers (Google, OpenAI) behind a swappable interface
API design & type safety — contract-first API so frontend and backend never drift out of sync
DevOps — CI/CD pipelines, Docker, reverse proxy configuration, automated TLS, server monitoring
Product thinking — feature scope, UX flows (onboarding tours, dictionaries sharing)

Tech stack

Vue 3 · TypeScript · Vite · Tailwind CSS · Turborepo · Bun · Hono · PostgreSQL · Drizzle ORM · Docker · GitHub Actions · Traefik · Redis

Highlights

Shipped and maintained a live, working production deployment (not just a local demo)
Designed and built the entire UI from scratch — no template or design kit used as a base
Built a fully automated CI/CD pipeline: every change is linted, type-checked, tested, and built before it reaches production
Designed the system so frontend and backend share types automatically, eliminating an entire class of integration bugs
Ran a real production/staging split on shared infrastructure with isolated environments