Projects

Self-hosted assistant for tasks, expenses, habits and journaling, built around a calendar-based context-awareness engine. A router sends each request to a different model (DeepSeek, Claude) depending on how hard the task is, so a small model handles what a big one doesn't need to. Telegram bot with text and voice (transcribed locally with Whisper) plus a React dashboard. It runs on a Raspberry Pi 5 under Docker Compose, exposed through a Cloudflare Tunnel with Zero Trust — no ports open on the home network.

Core module for handling tax documentation, designed to run on both Windows desktop and Android. It includes a remote-file module over SMB/CIFS and a validation engine driven by external JSON config, so fiscal rules can change without recompiling. Unit and integration tests with JUnit 5 and Mockito.

A study rebuild of the backend architecture: REST service in Spring Boot, centralised validation and transactional persistence with Spring Data JPA, containerised with Docker Compose. The React/Tailwind frontend is a demo only. Authentication (JWT/OAuth2) and broad integration tests were deliberately left out to keep the focus.

Desktop credential manager built zero-knowledge: AES-256-GCM encryption with PBKDF2-derived keys, and some care about how secrets sit in memory. The unit tests target attack vectors and data integrity, not just the happy path.