Product Engineer building privacy-first tools that I actually want to use.

Turn any PDF into an infinite drawing canvas

• The Problem: PDF annotation tools force you to upload sensitive documents to someone else's servers.
• The Solution: Browser-based annotation with pen-like precision. Zero uploads, total privacy.
• Impact: 3,000+ monthly active users across 175+ countries, 1,500+ desktop app downloads, 300+ GitHub stars.
• Tech: SvelteKit, Tauri (Rust), Canvas API, client-side processing, privacy-by-design

🔗 Try it: leed.my

Privacy-first email client with chat-style UX

• The Problem: Email UX hasn't evolved since the 90s. Users spend 2.5 hours daily drowning in cluttered inboxes.
• The Solution: Transforms messy email threads into clean, chat-like conversations with sub-50ms performance and zero-knowledge encryption.
• Impact: 40% faster email triage vs traditional clients, growing user base across multiple countries.
• Tech: Flutter, Supabase, PostgreSQL, IMAP/OAuth 2.0, end-to-end encryption

Grammar of graphics for Flutter

• The Gap: Flutter lacked a comprehensive, performant data visualization library.
• The Solution: 60fps GPU-accelerated rendering with intuitive grammar of graphics API.
• Adoption: 1,000+ monthly downloads with growing community adoption.
• Tech: Flutter, CustomPainter, GPU optimization, mathematical transformations

Privacy-first health journaling with AI

• The Problem: Health apps send sensitive data to remote servers. Users want predictions, not privacy violations.
• The Solution: On-device TensorFlow Lite inference, synthetic data training, HIPAA-compliant by design.
• Impact: 99% micro-F1 accuracy, <5ms inference time. Users stick around because predictions actually help.
• Tech: Flutter, TensorFlow Lite, Bi-LSTM networks, synthetic data generation

Capture anything with a single keystroke

• The Problem: Bookmarks pile up in folders you'll never revisit. Organizing feels like work.
• The Solution: Visual bookmarking with rich metadata extraction, offline-first storage, keyboard-driven workflows.
• Impact: Offline-first, privacy-focused architecture with local-first storage and visual masonry layout.
• Tech: SvelteKit, Chrome Extension API, client-side processing, metadata extraction

Ultra-lightweight with on-device AI subtitle generation

• The Problem: Video players are bloated with features you don't need. Subtitles require uploading to servers.
• The Solution: Zero UI experience with keyboard-first controls, on-device AI subtitle generation.
• Impact: Ultra-lightweight desktop app with native performance and cinematic viewing modes.
• Tech: Rust, Tauri, Svelte, on-device AI processing

AI assistant with shared memory across models

• The Problem: Using AI effectively means switching between models for different tasks, losing context each time.
• The Solution: Unified interface with context preservation, smart model routing, seamless switching.
• Impact: 350% faster AI workflows, 94% context retention across model switches.
• Tech: React, LLM APIs, context management algorithms, real-time state sync

Control the chaos, prevent the crashes

• The Concept: You control traffic lights in increasingly complex intersections. Toggle signals, manage flow, prevent accidents.
• The Challenge: Real-time traffic simulation with collision detection, optimized for smooth 60fps gameplay.
• Tech: Flutter, custom physics engine, state management, game logic optimization

Dart/Flutter • TypeScript • Python • Rust • JavaScript

I've been writing Dart for 5+ years and have shipped production apps with millions of interactions. Python and TypeScript are my go-to for rapid prototyping and backend work. Rust is newer but I've shipped two real products with Tauri.

Frontend: Flutter (mobile), SvelteKit (web), React, Astro, Chrome Extensions
Backend: Node.js, Python (Flask/FastAPI), Supabase, PostgreSQL
Desktop: Tauri (Rust), cross-platform native apps
Systems: Canvas API, WebGL, custom rendering engines

This is what sets my work apart. I don't just build features, I build products people can trust:

• Zero-knowledge encryption and end-to-end security
• On-device ML inference with TensorFlow Lite (no data ever leaves the device)
• Sub-50ms response times through aggressive optimization
• Privacy-first architecture from day one, not bolted on later
• Offline-first design so your data stays yours

Machine Learning: TensorFlow, TensorFlow Lite, on-device inference, synthetic data generation
Data Analytics: Statistical analysis, predictive modeling, A/B testing, user behavior analysis
Business Intelligence: Market analysis (15%+ product launch success improvement), data-driven decisions

My CS degree specialized in Data Analytics, and I apply it to actual product decisions, not just dashboards.

• Building products that respect user privacy while delivering ML-powered features
• Performance optimization (60fps on mobile, <50ms server response)
• Cross-platform development (one codebase, native feel everywhere)
• Shipping fast without breaking things

🌍 Global Reach

• Products used across 175+ countries
• 3,000+ monthly active users (LeedPDF)
• 1,500+ desktop app downloads (LeedPDF)
• 1,000+ monthly downloads (Cristalyse package)

⚡ Performance Achievements

• Sub-50ms email processing (15x faster than Gmail)
• 99% accuracy ML models with <5ms inference
• 60fps data visualizations on mobile devices

👥 Community Leadership

• 400+ member AI club president
• 89% positive feedback on technical workshops
• 370% increase in community engagement

📦 Open Source Contributions

• 450+ GitHub stars across projects
• Active contributor to Flutter ecosystem
• Technical documentation and tutorials

• BSc Computer Science (Data Analytics) – Asia Pacific University & De Montfort University
• 12+ years programming experience (started at age 12)
• President, AI Club – Led 400+ member community across 60+ nationalities

• Technical Workshop Leader – 180 average attendees, 89% positive feedback
• Product Launch Success – 15%+ increase in success rates through data analysis
• International Experience – Based in Budapest, EU work authorization ready

• English (Native) • German (Conversational) • Spanish (Elementary) • French (Beginner)

• WebGL/Three.js Advanced Techniques – Building immersive 3D portfolio experiences
• Edge Computing – Optimizing ML inference for mobile and web
• Privacy Engineering – Advanced encryption and zero-knowledge architectures
• Product Analytics – Data-driven product development methodologies

Recent Focus Areas:

• 🎯 Privacy-first architecture patterns
• 🧠 AI/ML model optimization for edge devices
• 🎨 Interactive 3D web experiences
• 📱 Cross-platform mobile development

"The products I build come from personal frustration. If I'm annoyed by something, chances are thousands of other people are too."

My approach:

• Privacy isn't negotiable: Your data belongs to you, not on someone's server
• Speed creates trust: When software responds instantly, people actually enjoy using it
• Simple beats clever: The best solution is the one people understand immediately
• Done beats perfect: Real feedback from real users beats endless internal debates

How I build:

• I write code that's easy to understand and maintain, because six months from now, I'll be that confused person trying to figure out what I was thinking
• I believe in thorough testing at every stage. Shipping fast doesn't mean shipping recklessly
• Good documentation isn't extra work, it's how you help future contributors (including yourself) hit the ground running
• Accessibility isn't a feature you add later. If it's hard to use for someone, it's not done yet

I'm always interested in connecting with fellow builders, especially around:

• Privacy-first product development
• AI/ML applications that actually help people
• Cross-platform mobile development
• Product engineering and user experience

📧 Email: reach@rudi.engineer
🌐 Portfolio: rudi.engineer (Interactive 3D experience)
💼 LinkedIn: linkedin.com/in/rudi-k
🐦 Twitter: @lofifounder

✏️ LeedPDF: leed.my
📱 DoublOne: doubl.one
📊 Cristalyse: pub.dev/packages/cristalyse
🌸 PinkRain: rain.pink
🔖 Golden Day: mygolden.day
🎬 Glucose: glucose.media
🧠 CaraML: caraml.app
🚦 Tuesdae Rush: tuesdae.games

✍️ Hashnode: hashnode.com/@lofifounder
📝 Medium: medium.com/@rudi-k
👥 Peerlist: peerlist.io/rudik