Haru
Built entirely by hand, Haru is a massive productivity ecosystem that has expanded to function almost like a specialized study operating system. The platform helps users research and learn topics faster by rewarding focused work and punishing distractions. It merges offline privacy and real-time online updates by running local AI models (via llama.cpp and fastText) alongside web search tools. Key features include localized RAG across user notes, cognitive minigames, Todoist/ActivityWatch integrations to track computer usage, built-in Excalidraw, advanced calculators, Pomodoro timers, and speech-to-text/text-to-speech engines that generate clean, Obsidian-compatible markdown notes. Active development was completed to focus on smaller, targeted sub-projects after extracting immense learning value from this codebase.

About This Project
Designing an all-encompassing productivity ecosystem that tracks workspace state, compiles markdown summaries, runs local AI inference, and incentivizes focus while eliminating distractions.
Engineered a custom desktop environment using SolidJS and Tauri. Orchestrated llama.cpp for offline RAG, integrated OS-level window and activity tracking via ActivityWatch/Todoist, and implemented speech transcription pipelines to output markdown compatible with Obsidian.
A highly customized 'productivity OS' that unifies notes, tasks, calculators, and mindmaps into a single window. The project served as a massive systems design playground before being completed in favor of smaller modular tools.
AI & Full-stack Developer
2025
Finished
Personal
Technology Stack
Project Story
Designing an all-encompassing productivity ecosystem that tracks workspace state, compiles markdown summaries, runs local AI inference, and incentivizes focus while eliminating distractions.
Engineered a custom desktop environment using SolidJS and Tauri. Orchestrated llama.cpp for offline RAG, integrated OS-level window and activity tracking via ActivityWatch/Todoist, and implemented speech transcription pipelines to output markdown compatible with Obsidian.
A highly customized 'productivity OS' that unifies notes, tasks, calculators, and mindmaps into a single window. The project served as a massive systems design playground before being completed in favor of smaller modular tools.
Insights & Takeaways
Highlights
- Functions as a comprehensive, hand-built 'productivity operating system' housing tools like Excalidraw, Pomodoro, and cognitive minigames.
- Features OS-level activity tracking via Todoist and ActivityWatch integrations to reward focus and warn of distractions.
- Generates Obsidian-ready markdown notes through integrated Speech-to-Text (STT) and Text-to-Speech (TTS) pipelines for audio files and video playlists.
Challenges
- Orchestrating multi-layered local binaries (llama.cpp, fastText) and speech model pipes under a single SolidJS UI without degrading responsiveness.
- Connecting third-party productivity APIs (Todoist, ActivityWatch) to local database records dynamically.
Lessons Learned
- Building a massive, monolithic 'personal OS' provides unmatched architectural training, but also proves that small, single-purpose utilities are often more maintainable.
Related Work
Case Study
Auto Shutdown
Rust + React desktop app to automate PC shutdowns by timer, schedule or idle state.
Case Study
Azkari
Lightweight desktop app that displays Azkar reminders based on time of day, built with Tauri, SolidJS, TypeScript and Rust.
Case Study
FanumTag
Blazing fast, 100% offline AI tool for batch-renaming media collections (audio, video, docs, images) based on their actual content.