One honest line a day.A tiny habit that compounds.
Write in under a minute
Capture up to 333 characters while the day is still vivid.
Encrypted with your passphrase
Unlock the vault with a code only you know. Without it, even we just see ciphertext.
See the story build
Automatic recaps turn your lines into a narrative that sounds like you.
Guided setup for brand-new writers
Curious before you commit? Launch the onboarding assistant to tour visitor mode, learn how sign-up works, and see what happens after you confirm your email.
When you finish creating your account and log in, the tour automatically returns inside the app to explain Today, History, Summaries, and Settings.
Locked with a passphrase only you know
OneLine is now fully end-to-end encrypted. You pick the passphrase; your browser derives the key and encrypts every line with AES-GCM before anything leaves your device.
- No passphrase, no access: We never see or store it. Without your code, the vault stays locked.
- Unlock before you write or read: Saving, streaks, and history all require the vault to be open locally.
- Lose the passphrase, lose the data: That’s the trade-off of true privacy. Use a password manager if you need backup.
1. Derive your key locally
passphrase + salt → PBKDF2 (200k iterations) → AES-256 key
2. Encrypt every entry
AES-GCM(key, 96-bit IV) → ciphertext stored in Supabase
3. Server only sees this
{
"content_cipher": "b64...",
"iv": "b64..."
}Plain text never reaches our servers or logs.
Exactly how OneLine works
Capture the signal
End each day in the Today screen with one true line. The 333-character cap keeps it sharp and easy to sustain.
Stitch the story
Entries are timestamped, encrypted client-side, and stored under EU-grade privacy. Summaries refresh monthly, quarterly, and every 1 January automatically.
See yourself clearly
OneLine becomes a living archive of your wins, lessons, and mindset shifts — ready for founder updates or personal check-ins.
Own your words
Export or delete anytime. You control your data; we simply help you build a habit that compounds.
Inside the daily loop
- •Reflect fast: Type 2–3 sentences, tag the mood if you want, hit save.
- •Stay accountable: See streaks, gentle nudges, and your most used themes build over time.
- •Unlock the story: Summaries refresh monthly, quarterly, and on 1 January automatically — ready to share or keep private.
Keep your streak — unlock your companion
Consistency matters more than word count. OneLine keeps the daily ritual friendly so you can show up again tomorrow.
- See the streak glow: Celebrate consecutive days without anxiety — miss once and you start fresh, no shaming.
- Meet your guide: A digital companion evolves as you log more days, mirroring your growth mindset.
- Unlock rewards: New companions and ambient themes appear at 7, 21, 60, and 120-day streaks.
Next badge at 21 days
Companion
Lumen the Fox
Unlocked at 7 days. Keep logging to evolve your guide and reveal new environments.
Designed for daily momentum
Micro-entries under 333 characters keep you honest without draining your energy. Every pixel is tuned to get you in and out in under ten seconds.
Private by architecture
Entries are encrypted with a key derived from your passphrase, so servers only keep ciphertext. Export, delete, or automate yearly recaps whenever you want — your data stays under your control.
Narratives that feel like you
Generate a month, quarter, or year in review — plus the automatic New Year recap — with tone, voice, and highlights tuned to your entries.
Week one
Feel the relief of closing each day with one honest, sub-333-character reflection. The streak builds momentum, not pressure.
Day 30
Patterns surface. You spot repeatable wins, mindset shifts, and friction before they snowball.
Quarter’s end
One click — or the automatic 1 January generation — gives you a founder update, performance recap, or personal story that sounds like you wrote it.
How OneLine fits your day
Write under 333 characters
Open Today and capture the highlight, tension, or lesson in two short sentences. Five to ten seconds is all you need.
Keep the streak (and grow)
Tomorrow, do it again. The constraint builds growth-mindset reflection: what worked, what changed, what to try next.
Generate a story
When you want perspective, create a summary for the last month, quarter or year — or let OneLine produce your year-in-review the moment January arrives. Clean, faithful, readable.
Why the science backs micro-journaling
OneLine stands on decades of behavioural research. Keeping the ritual short means you actually do it; weaving stories from your own words gives you insight without the blank-page anxiety.
- Expressive writing boosts wellbeing. Dr. James Pennebaker’s studies show that brief, honest reflection improves immune function and emotional processing. OneLine’s daily constraint mirrors that proven cadence.
- Gratitude + growth mindsets compound. Research from Emmons & McCullough and Carol Dweck links consistent gratitude and growth-focused journaling to higher resilience, motivation, and long-term goal attainment.
- Reviewing wins fuels performance. Harvard Business School findings on the “progress principle” show that documenting small wins increases engagement and creativity. Your automatic stories spotlight those wins for you.
“My founders’ updates used to take a Sunday afternoon. Now I write one line a day, click generate, and the story sounds like me — detailed, not fluffy.”
Built for discretion
We operate from Madrid under EU privacy law and give you full control over your words. The vault stays locked behind the passphrase you choose — we can’t reset it, and we never transmit it. Automations run with your permission, exports are instant, and deletion is irreversible — exactly as it should be.