I'm Building a Life OS That Actually Respects Your Privacy

I've been quietly building something in the background for the past few months.

It started as a simple journaling app. Now it's turned into what I'm calling a "Life OS." A single system that handles my journal, tasks, calendar, contacts, and personal organization. All running locally on my machine. All encrypted. No cloud sync to some company's servers.

The quick version. I'm building a privacy-first personal productivity system with local AI, end-to-end encryption, and zero external dependencies. Your data never leaves your device unless you explicitly choose to sync it yourself.

Why I Started Building This

Honestly? I got paranoid.

I was using Notion for task management, Day One for journaling, Google Calendar for scheduling, and a random contacts app to track birthdays. Four apps. Four companies with access to my personal thoughts, schedules, and relationships.

Then I read Notion's privacy policy. Really read it.

They can access your content. They use it to "improve their services." Your private journal entries, your task lists, your second brain. All sitting on someone else's servers, processed by algorithms you'll never see.

I'm not a tinfoil hat person. But when I journal, I write things I don't want anyone to read. Ever. When I track my goals and habits, that's personal data about my psychology. When I note relationship details about friends and family, that's not something I want feeding an ad algorithm.

So I started building my own thing.

What This Life OS Actually Does

Let me break down what I've been working on.

The Journal

This is where it started. A simple, encrypted journal that runs entirely on your machine.

I've tried every journaling app out there. Day One, Obsidian, plain text files, even a custom Notion setup. They all had the same problem. Either they sync to the cloud, or they're so bare-bones that I stopped using them after a week.

My journal has..

• Encrypted entries that only you can decrypt with your master password
• Full-text search that works on encrypted content (this was a pain to build)
• Daily prompts that actually help you reflect, not just "what are you grateful for" nonsense
• Mood tracking and patterns over time
• Voice-to-text for when you don't feel like typing

The entries are stored in a local SQLite database, encrypted with AES-256. Nobody can read them without your password. Not me, not Apple, not your nosy roommate.

Tasks and Projects

Look, I've built task management systems before. I even wrote about the mistakes I made building one. This time, I'm doing it differently.

The task system has the basics. Due dates, priorities, projects, tags. But what makes it different is the gamification layer.

Here's what I mean by gamification..

You earn experience points for completing tasks. Harder tasks give more XP. You level up over time. You unlock achievements for streaks and milestones.

I know, it sounds childish. But it works.

Before adding gamification, I'd open my task app, feel overwhelmed, and close it. Now I open it to see how close I am to the next level. I actually want to check things off because I get that little dopamine hit.

The data backs this up too. In my testing, I completed about 40% more tasks in weeks where I actively used the gamification features. Your mileage may vary, but for me, turning productivity into a game changed everything.

The Calendar

The calendar is simple on purpose.

I don't need Google Calendar's 47 features. I need to see what I have today, this week, and this month. I need to add events quickly. I need reminders that actually work offline.

That's it.

The calendar integrates with the task system. Tasks with due dates show up on the calendar. You can drag and drop to reschedule. It sounds basic because it is. But it works without an internet connection, and that's the point.

Contacts and Relationship Tracking

This is the feature I'm most excited about, and the one I've seen almost nobody else build well.

I'm terrible at remembering birthdays. I'm worse at remembering the important details about people. What are their kids' names? When did they mention they were going through that rough patch? What was that project they were excited about last time we talked?

The contacts feature tracks..

• Basic info like phone, email, address, birthday
• Important dates beyond birthdays. Anniversaries, work milestones, whatever matters
• Relationship notes that you add after meetings or conversations
• Reminder triggers so you actually reach out before someone's birthday, not three days after

I've been using it for a couple months now, and it's already saved me from forgetting two close friends' birthdays. Small win, but those things matter.

The AI That Runs Locally

This is the technically interesting part.

I integrated a small language model that runs entirely on your machine. No API calls. No sending your journal entries to OpenAI. The model lives on your device and processes your data locally.

Why this matters..

Most AI-powered productivity apps work by sending your data to a cloud API. Your private thoughts get processed on someone else's server. Even if they claim not to store it, you're trusting their word.

My approach is different. The AI model is a small, efficient one. Think 7-8 billion parameters, quantized to run on consumer hardware. It's not as smart as GPT-4, but it's smart enough for personal productivity tasks.

And it has RAG (Retrieval Augmented Generation) over your personal data.

What that means in practice..

You can ask it things like..

• "What was I working on last month?"
• "When is Sarah's birthday?"
• "What were my main goals from my January journal entries?"
• "Summarize my tasks for this week"

The AI searches your local data, finds the relevant information, and generates a response. All without ever touching the internet.

I'll be honest. The quality isn't perfect. Local models still lag behind cloud APIs. But for personal queries about your own data, they're good enough. And the privacy tradeoff is worth it.

Why Local-First Software Matters

I've been thinking a lot about this lately.

We've gotten used to everything living in the cloud. Documents, notes, photos, contacts. All synced across devices through someone else's servers.

It's convenient. I get it. But there's a cost we don't think about.

The problems with cloud-first apps..

• They require internet to work fully
• They can change pricing or features at any time
• They can shut down entirely (RIP Google Reader, Sunrise Calendar, and dozens of others)
• They have access to your data, even if they promise not to misuse it
• You can't truly delete anything. It lives in backups somewhere

Local-first apps flip this..

• Work fully offline, sync when you choose
• Your data exists on your hardware, period
• No subscriptions that can increase yearly
• No company can lock you out of your own information
• Genuine deletion is possible

I'm not saying cloud sync is always bad. But for personal, private information? I want it local first, with optional sync I control.

The Technical Stack (For Fellow Developers)

For those curious about how I'm building this..

Frontend. Tauri with React. Tauri gives you native desktop apps with web tech, but without Electron's bloat. The app is about 15MB, not 300MB.

Database. SQLite with SQLCipher for encryption. Everything is encrypted at rest. The database file is useless without your master password.

Local AI. Running llama.cpp with a quantized model. Currently testing different models to find the best balance of quality and speed. Mistral 7B is working well so far.

RAG Pipeline. Custom embeddings stored locally. When you ask a question, it searches your data using vector similarity, then passes relevant context to the language model.

Cross-platform. Works on Mac, Windows, and Linux. Same codebase, same features everywhere.

If you're interested in building local-first apps, I highly recommend reading the Local-First Software manifesto by Ink & Switch. It articulates the philosophy better than I can.

What I've Learned Building This Solo

Building something this ambitious alone has taught me a few things.

Scope creep is real, but sometimes it's good.

I started with "just a journal app." Now I'm building a full Life OS. That sounds like classic scope creep. But each feature I added solved a real problem I had. The expanded scope makes the product more valuable, not more bloated.

The key is knowing when to stop. I've got a list of features I'm explicitly not building. No team collaboration. No mobile app (yet). No cloud sync beyond what you set up yourself. Saying no to things keeps the project manageable.

Privacy features are hard.

Encryption seems simple until you actually implement it. Key management, secure storage, making search work on encrypted data. Each of these was its own rabbit hole.

I spent two weeks just on the search feature. Trying to make full-text search work on encrypted content without decrypting everything every time. Eventually landed on a solution using encrypted indexes, but it wasn't obvious.

Local AI is more usable than I expected.

When I started, I assumed local models would be too slow or too dumb to be useful. They're not. On a modern MacBook, inference is fast enough to feel responsive. And for personal data queries, you don't need GPT-4 level reasoning.

The key insight is that your personal data is the context. You're not asking the model to be creative or do complex reasoning. You're asking it to find and summarize information it already has access to. That's a much easier task.

What's Next

I'm still building. The core features work, but there's polish needed before I'd let anyone else use it.

Coming soon..

• Mobile companion app (read-only initially, to keep scope small)
• Optional encrypted sync between your own devices (using your own server or a service like Syncthing)
• More gamification features like streaks, challenges, and custom achievements
• Better AI prompts for journaling and reflection

Not on the roadmap..

• Team features
• Public sharing
• Cloud hosting
• Subscriptions

This is a personal tool, built for individuals who care about privacy. I want to keep it that way.

Should You Build Your Own Life OS?

Maybe.

If you're a developer and you care about privacy, building your own tools is incredibly satisfying. You control everything. You own your data. You can customize every detail.

But I won't pretend it's easy. This project has taken months of my spare time, and it's still not done. If you just want a privacy-respecting task manager, there are simpler options.

If you want to start simpler..

Build a single feature first. Just the journal. Or just the task manager. Ship something small, use it daily, then expand from there. That's what I did. The Life OS grew organically from a journaling app I actually wanted to use.

I wrote about this approach in my post on building side projects while working full-time. The key is consistent small progress, not weekend marathons.

FAQ

Why not just use Obsidian?

Obsidian is great. I use it for some things. But it's primarily a note-taking tool, not a unified Life OS. I wanted tasks, calendar, contacts, and AI all integrated in one place. Also, Obsidian's sync is cloud-based (though they do offer end-to-end encryption on paid plans).

How do I sync between devices without cloud?

You have options. Syncthing lets you sync folders directly between devices on your local network or over the internet. You could also use your own NAS or home server. The key is that you control the sync, not a third party.

Is the AI actually useful without internet?

Yes, but with caveats. It's good at searching your data, summarizing entries, and answering factual questions about your life. It's not as good at creative tasks or complex reasoning. For a Life OS, the former matters more than the latter.

What happens if I forget my password?

You lose access to your encrypted data. That's the tradeoff with true encryption. I'm building in some recovery options (like a printed recovery key), but fundamentally, if you forget your password and lose your recovery key, the data is gone.

When will this be available?

I don't have a timeline. It's a side project I'm building for myself first. If I release it publicly, it'll be after I've used it daily for at least 6 months and ironed out the rough edges.

Will it cost money?

Haven't decided. Probably a one-time purchase if I release it, not a subscription. I hate subscriptions for personal tools. Your Life OS shouldn't require monthly payments to access your own data.

Final Thoughts

Most productivity apps treat your personal data as an asset to monetize.

I'm building something different. A tool that respects that your journal entries, your relationships, your goals. That stuff is private. It should stay on your hardware, under your control, encrypted so that only you can access it.

It's been a lot of work, and there's more to do. But every time I open the app and see my encrypted journal, my tasks, my calendar, all in one place with an AI that can search through it without phoning home?

That's worth the effort.

If you're interested in local-first software, privacy-respecting tools, or just want to follow along as I build this thing, I'll be posting updates here. There's something satisfying about building something just for yourself, even if nobody else ever uses it.

Sometimes the best software is the software you build because you needed it.