Seven Months of Vibe Coding: How I Built a Privacy-First Journal App with an AI Pair Programmer
The full story behind MoodHaven — the security decisions, the peer sync rabbit hole, the Wear OS companion, and what building with an AI pair programmer actually looks like in practice.
Read on kennethlacroix.me
June 13, 2026
We Tried to Break Into Our Own App — On a Real Phone
We installed MoodHaven on an everyday Android phone and spent a day trying to read your journal, steal your password, and intercept your data. Your entries stayed encrypted, your text never left the device, and biometric unlock held. Here's the honest accounting — including the small things we tightened up.
June 10, 2026
Activity Tagging: Seeing What Actually Affects Your Mood
Tracking activities alongside mood turns a journal into a feedback loop. After a few weeks you can see — not guess — which habits are helping and which aren't.
June 9, 2026
What Changing Your Password Actually Does — and Why It's Safe to Interrupt
In MoodHaven your password isn't stored anywhere — it's the key that unlocks everything. So changing it re-encrypts your whole journal. Here's what that means, and why an interrupted change always rolls back cleanly to your old password.
June 9, 2026
Why Local-First Is the Right Architecture for a Private Journal
Cloud-first apps trade your data for convenience. Local-first flips that — you get the convenience, and your data never leaves until you decide it should.
June 8, 2026
What We Actually Send to the AI (and What We Don't)
MoodHaven's AI features work from metadata — mood scores, patterns, frequency. Your journal text never leaves your device. Here's exactly what goes out and what stays in.
June 7, 2026
How We Stress-Tested the Privacy in Your Journal — Ten Rounds of Attacks
Ten rounds of real attacks against our own private journaling app, on tools we built from scratch. The one thing it exists to protect — your entries — was never exposed. Here's the honest accounting.
May 26, 2026
StillHaven — Settle Before You Write
v1.1 ships StillHaven, a bilateral audio stimulation companion built into MoodHaven Journal. A short session before you write can make the difference between a defensive entry and an honest one.
May 26, 2026
What Is StillHaven, and Why Does It Live Inside a Journaling App?
I built StillHaven because I kept noticing the same thing: the entries I wrote right after something hard were the least honest ones. Not because I was lying. Because I was still too activated to actually feel what had happened.
May 24, 2026
MoodHaven Journal v1.0 — Shipped
A year of building in public. 702 automated tests. A journaling app that runs entirely on your device, ships to four platforms, and keeps your words yours.
June 20, 2025
Reflections on Building MoodHaven Journal
Every project teaches you more than you expected. Building MoodHaven has been as much a personal journey as a technical one.
June 13, 2025
MoodHaven on Mobile: Browser App and Wear OS Companion
Your thoughts don't wait until you're at your desk. Here's how MoodHaven goes with you — in your browser and on your wrist.
June 6, 2025
Choosing Self-Hosting for Journals: Why It Matters
Where your journal lives matters. Self-hosting means replacing blind trust in someone else's infrastructure with verifiable control over your own.
May 30, 2025
How MoodHaven Insights Will Work
Insights that empower you — without ever exploiting your private thoughts. All analysis stays on your device, always.
May 23, 2025
How MoodHaven Protects Your Journal
How MoodHaven keeps your private thoughts safe — with real encryption, real integrity, and no hidden compromises.
May 16, 2025
Our Privacy Philosophy at MoodHaven
Because your thoughts should belong to you — not to us, not to anyone else. Privacy isn't a feature we bolt on later.
May 8, 2025
Protecting the Pause: Why MoodHaven Was Built for Stillness
In a world where even wellness apps are gamified, we believe emotional well-being deserves something gentler.
May 5, 2025
The MoodHaven Roadmap: What's Next
What shipped, what's coming, and how the project has grown — from the first commit to v1.0.
May 2, 2025
Why I Built MoodHaven
Most journaling apps quietly harvest your data or tie you to someone else's server. I wanted something different — a journal that truly belongs to you.
April 27, 2025
Welcome to MoodHaven Journal
A quiet place to reflect, grow, and breathe again in a world that often feels overwhelming. Thank you for being here at the beginning.
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