Developer Builds Personal OS App with Claude Code and Mowgli in 3 Hours

A developer documented building a personal OS application called Longinus in under 3 hours using AI coding tools. The app integrates multiple communication platforms and provides AI-powered organization features.
Project Details
Longinus is a personal OS application that:
- Integrates Slack, WhatsApp, and personal feeds
- Digests daily/weekly activity summaries
- Supports saving items as "Sparks" (todos, reminders, journal entries, bookmarks)
- Includes an AI chat interface for discussing saved Sparks
- Aims to reduce context switching between different AI tools
Development Process
The developer used:
- Claude Code on a Max plan with Opus 4.6 for coding
- Mowgli (https://mowgli.ai) for design specification and to reduce token consumption
Time breakdown:
- 1 hour for design and specification
- 2 hours for building, testing, and implementation
Current Status and Future Plans
The project is available on GitHub at https://github.com/othersidejann/longinus. The AI features are described as "still rough around the edges," with synthesis and other AI improvements planned for future development. The developer welcomes pull requests and ideas for AI feature enhancements.
The final design can be viewed at https://app.mowgli.ai/projects/cmm4z67af000i01mp6o893qia.
📖 Read the full source: r/ClaudeAI
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