Stack
One login. Every tool. Complete control.
Cairn Stack is the central portal where your firm manages identity, subscriptions, and access to every Cairn app. Sign in once — everything is connected.
The Hub
Everything connects through Stack.
Log in once. Your identity, your team's roles, and your subscriptions flow to every app automatically. No separate accounts, no repeated setup.
Stack What Stack Does
Three things. Nothing else.
Stack is not a workspace. It's the infrastructure that makes every workspace possible.
Identity & Access
Auth0-powered single sign-on. Invite team members, assign roles at the firm level, and those permissions flow to every app automatically. No per-app user management.
Subscriptions & Billing
Browse the Cairn catalogue, subscribe to the tools your firm needs, and manage everything from one dashboard. Module-level granularity, one invoice, Stripe-powered.
Seamless App Launching
Click an app tile and you're inside it. A signed handoff token transfers your identity in under a second. No re-authentication, no loading screens, no visible seams.
Your data gets its own walls.
Every firm gets its own database, its own containers, its own isolated environment. Stack is the only multi-tenant component — and it never stores your client data. This isn't row-level filtering. This is real isolation.
The Foundation
Every Cairn app works through Stack.
Identity, billing, and access — managed once, inherited everywhere.
Cairn Statements
AI-powered bank statement processing and QuickBooks sync for accounting firms.
Learn moreCairn Returns
Coming SoonPersonal and business tax return management for accounting firms.
Cairn Docs
PlannedClient-facing document upload portal for accounting firms.
Cairn Toolbox
PlannedAccounting calculators and quick-reference tools.
Ready to build your stack?
We're onboarding firms individually to ensure every experience is exceptional. Leave your info and we'll reach out.