Prototype In development · built with Claude

Say it. Haru understands,
and helps get it done.

Haru, Korean for "a day", is a Korean-language personal AI assistant in development for natural voice conversations, information retrieval, desktop actions and study. You talk to it, and it looks things up, opens apps and sites on your PC, keeps your schedule and reminders, and helps you review lectures.

See the features Open the web prototype (password)
haru · prototype — windows
Haru on Windows: a Bitcoin chart, a study playlist, the particle orb and the F1 control panel
Real screenshot · the Haru prototype on the developer's PC (chart, study music, F1 control panel) · "JARVIS" on screen is the development codename

Under the hood

Preview

58 seconds with Haru.

An unedited screen recording. Haru answers by voice, briefs the news, then opens a chart and a study playlist on request.

haru-demo.mp4 · 0:58
Unedited screen recording · sound is off at first, turn it on in the player · "JARVIS" on screen is the codename
Features

From conversation to desktop work, and study too.

Haru is a general personal assistant, not a study-only app. Learning support is one area among several. Each feature shows its current status.

ImplementedPrototype · being verifiedPlanned
Voice conversationImplemented

Ask by voice, hear the answer.

Wake it with a wake word or a double clap, or switch on always-listening and just talk. Speech is transcribed on the PC with faster-whisper, and replies are read aloud in a voice generated on the user's own GPU. You can interrupt it mid-sentence. Follow-up conversation is still being improved.

wake worddouble clapbarge-inon-device TTS
InformationImplemented

The facts you need, fast.

Web search, weather and air quality, currency, Wikipedia summaries, holidays and tech news, all through real free APIs. Live facts come from tool results, not guesses.

Desktop actionsImplemented

Your PC, by voice.

It launches registered apps, sites and games, opens sites in your logged-in Chrome profile, plays YouTube or Spotify music, and handles do-not-disturb, in-app notes and window layout. Common commands are handled instantly by local rules.

Schedule, notes and memoryImplemented

It remembers so you don't have to.

Save an event by voice and it reminds you 10 minutes before and at the start. It reads your phone calendar (ICS) for briefings and keeps memory on this PC. Writing to external calendars and server-side long-term memory don't exist yet.

Markets and alertsImplemented

Analysis only, never trades.

Chart wall, economic calendar and news, order-flow and quant analysis, Bitcoin on-chain data and pension-fund disclosures. Price and deadline alerts are checked by code, not a model. No performance claims.

Study materialPrototype · being verified

Lectures into review material.

Class mode (silent marking and a sourced review) is implemented on the PC. A study helper built as a Claude artifact makes notes, practice questions, flashcards, mind maps and PDFs. So far it has only been tested with stub responses.

Recording and transcriptionPrototype · being verified

A lecture recording page.

A separate page with recording, local recovery, Groq Whisper transcription and timetable recognition. It isn't deployed yet and hasn't been verified on a real iPad or with real model responses.

Account connectionsPlanned

Safe links to your own accounts.

Per-user sign-in comes first. After that comes connecting email, calendar and Notion accounts the user approves. Today the prototype is protected by a single shared password, so sign-in has to change before any personal accounts are linked.

Examples

Just say it.

What's the weather today?
The weather tool fetches the current temperature, feels-like and a 4-day forecast, then answers out loud. With no city named, it uses the configured one.
Open Chrome
It launches the app registered in config right away. For an unregistered app it explains how to add it.
Remember team project, Oct 20 at 3
It saves the event, then mentions it in that day's briefing and speaks up 10 minutes before and at 3.
Find today's Bitcoin news
It searches the web, summarises the key points and shows the source links as cards.
Make key concepts and questions from this PDF
The study-helper prototype drafts notes and practice questions. Its quality hasn't been fully verified with real Claude responses yet.
Example phrases. These are not transcripts of real conversations.
Screens

Not a mockup. The real thing, in use.

Unedited screenshots from the developer's Windows PC. "JARVIS" on screen is the codename used during development; the product name is Haru.

Haru responding with a green orb while a study playlist plays
Responding. The orb turns green while Haru speaks. A voice request opened a focus playlist next to a chart and the F1 study panel.
Haru listening with a red orb and the conversation on the right
Listening. The orb glows red while the Python voice engine hears you. The conversation stays on the side.
Quant desk window with walk-forward results, a study video and a notes window
Quant desk. Walk-forward results for each strategy, next to a lecture video and in-app notes.
Development and update panel showing Claude Code CLI connected and change history
Development and updates. The Claude Code CLI is connected. Each change Haru made to itself is listed with its files and a one-click undo.
Second monitor chart wall with ten charts and an S&P 500 heatmap
Second-monitor chart wall. Ten charts and an S&P 500 heatmap, laid out automatically.
Claude's role

What Claude does, and what it doesn't.

Fast local rules, Claude's judgment and other models each have their own part. Here is the split.

i.

PC conversation brain

Open questions go to Claude Code, logged in on the PC and allowed to read and web-search only. If Claude Code is missing or fails, a free Groq model answers instead.

Implemented · connection seen on the developer's PC
ii.

Development engine

Spoken feature requests go to the Claude Code CLI, which edits a copy of the app. Syntax checks, test runs and user confirmation come before it's applied, with automatic rollback.

Implemented · real change history
iii.

Web prototype

The web server has a Claude API path with tool use and web search. The current deployment has no Claude key set, so Groq answers today.

Path built · real Claude calls not yet verified
iv.

Study helper

A Claude artifact flow analyses lecture material into notes, practice questions, flashcards, mind maps and PDFs.

Prototype · tested with stub responses only

What Claude doesn't do: transcription is Whisper (faster-whisper on the PC, Groq on the web and recording page). Request types (analysis, research, action, development), common commands and alerts are code rules. The agent nodes on screen are visual only.

Status

Where things stand.

M

Minjun Park · 박민준

A university student and solo developer in South Korea, building Haru before registering a business. No users, revenue or funding yet.

75+commits since Oct 5, 2026
21klines of code
70+automated test files (mostly with stub responses)
3parts: PC app, voice engine, web

Implemented

  • Voice conversation (wake word, always-listening, barge-in)
  • Seven information tools plus web search
  • App and site launching, music, do-not-disturb
  • Schedule reminders, briefings, local memory
  • Task log with pause, resume and undo
  • Claude Code development engine with rollback

Verified / not yet

  • Verified: runs on the developer's PC (screens and video above)
  • Verified: web deployment, password protection, real-API tool tests
  • Not yet: real Claude API calls on the web
  • Not yet: measured speech accuracy, iPad recording
  • Not yet: study-helper quality with real Claude

Next

  • Per-user sign-in
  • Approved email, calendar and Notion connections
  • Server-side long-term memory
  • A small test with student users
  • Measure cost per request, latency and task completion
Contact

Feedback and testers are welcome.

Product feedback, beta testing and partnerships are all welcome. The founder replies personally.

minjun@heyharu.kr