The first mail client and archive built as one tool. Not two apps stitched together — one engine that reads, organizes, and preserves every email you've ever received. Across every account. Forever.
Every mail client treats your archive as someone else's problem. Your host migrates servers — mail gone. Your provider shuts down — mail gone. You switch clients — good luck with that export. You're left managing a mail client and a separate backup tool, hoping they stay in sync, hoping the formats stay compatible, hoping the server you're renting keeps your fifteen years of correspondence alive.
Cairn is the answer to a question that shouldn't need asking: where is my email when the server disappears? It lives on your drive, in a single SQLite database that belongs to you. Not your hosting provider. Not your IT department. Not a cloud service that might pivot next quarter. You.
Formula 1 fast — at scale. Cairn uses SQLite FTS5 with porter stemming, the same engine that powers iOS Spotlight. One unified database. One index. Every account, every folder, every message — searched in the time it takes your screen to refresh.
No separate backup app. No manual exports. Every message is archived the moment it's synced. Read your email and preserve it in the same action, in the same window, from the same database.
Your mail database is a single SQLite file on your hard drive or external SSD. No cloud. No subscription. No telemetry. Servers go down, hosts disappear, providers pivot — your archive doesn't care.
Manage over 100 IMAP accounts simultaneously with connection pooling and incremental sync. Import your existing accounts from Mailmate, Thunderbird, Apple Mail, or Outlook.
Click any message — instantly see every email from that sender across every account you own. Not just the current folder. Not just the current account. Everything, everywhere, in one pane.
Color-coded tags with automated rules. Smart folders that build themselves. Import your existing Mailmate tags with full color preservation. Organize at the speed of thought.
Create calendar events from email. Send messages to DEVONthink.* Open attachments in the right app. Use tools like SpamSieve,* BusyCal,* Fantastical,* OmniFocus,* and Things* — Cairn connects to your workflow.
If you receive 800 emails a day and 400 of them are junk, the last thing you want is an archive that dutifully preserves every piece of garbage alongside every piece of correspondence that matters. Cairn draws a hard line.
Every message outside the junk boundary is archived permanently by default. Your inbox, your sent mail, your folders, your threads — persistent, searchable, yours.
Junk and spam folders are firewalled from your archive. SpamSieve* integration catches what the server misses. You decide what gets purged — Cairn handles the rest.
Enter your IMAP server details and credentials for each account. Cairn supports SSL, STARTTLS, custom ports, and per-account polling intervals. Import server settings from Mailmate, Thunderbird, Apple Mail, or Outlook to save time — then add your passwords in-app.
Cairn connects to every IMAP server and pulls every message from every folder into one unified database. Read-only — Cairn never modifies, moves, or deletes your mail on the server. Your archive grows with every sync. Junk stays outside the wall.
Full-text search across your entire history in under 5 milliseconds. Tag, flag, and organize across account boundaries. When the server eventually goes away — and it will — your email doesn't go with it.
Never let a server or a host determine the existence of your mail.— The Cairn Principle
Cairn is in active development. One-time purchase. No subscription. No cloud.