Migration service
Move your legacy HubSpot CRM cards to modern app cards
HubSpot has announced a sunset deadline of October 31, 2026 for legacy CRM cards. If you are a small app vendor or agency with cards built on the classic CRM cards API, this is a fixed-scope migration path to React app cards on the Projects 2025.2 platform — starting with a paid audit, not a sales call.
What is being sunset, and what breaks
HubSpot has announced that legacy CRM cards — the "classic" UI extensions that render on record pages — are being sunset on October 31, 2026. The replacement is React app cards on the Projects 2025.2 platform, which changes how cards are built, served, and authorized. Integrations that still depend on the legacy card surface after the deadline stop rendering where your users expect them. The date and terms are HubSpot’s to set; verify current details against HubSpot’s developer documentation. Our position is operational, not urgent for its own sake: plan the migration before the deadline forces an unplanned one.
Who this is for
Small HubSpot app vendors and agencies with legacy-card exposure. These are the situations the audit is built around.
- Your app renders record-page cards through the legacy CRM cards API ("classic" UI extensions), and nobody on the team has scoped what the replacement platform requires
- The card still works today, so the migration keeps losing to feature work — until the sunset date turns it into an unplanned rewrite with customers watching
- Your OAuth scopes, serverless functions, and card payloads were designed years ago, and no one has mapped which parts carry over to app cards and which do not
- You maintain cards for client portals as an agency, and each portal needs an inventory before you can quote the work honestly
48-hour migration audit — $1,500, credited toward implementation
The audit is the first deliverable, not a discovery call. Within 48 hours of access you get a document set you can execute with us or with your own team. The $1,500 fee is fully credited toward implementation if you proceed.
- Full inventory of your legacy cards and extensions
- Projects 2025.2 migration plan
- API and OAuth scope mapping
- Pilot rollout flag plan
- View-swap plan
- Rollback risks
- Fixed implementation quote
Email support@clevercat.app with the subject "Migration Audit Request", or use the support form.
Implementation from $5,000
A simple single-card migration — one legacy card rebuilt as a Projects 2025.2 app card, rolled out behind a pilot flag with a view-swap plan and documented rollback path — starts at $5,000, quoted fixed in the audit.
Explicit boundary: multi-card migrations, serverless-function work, and complex OAuth changes are not covered by the starting price. They are scoped in the audit and quoted separately, so the number you approve is the number you pay. No implementation work begins before you accept a quote.
We run on the platform we migrate you to
CleverCat’s three production apps are built as modern Projects 2025.2 apps — sidebar, tab, and preview app cards, workflow actions, and OAuth installs. The cards, scopes, and boundaries are documented on this site; the same rollout discipline (test slice first, staged expansion, validation checkpoints) is what the audit plans for your cards.
DupliCat
CRM record-card entry surfaces — sidebar card and preview card — plus a workflow action, installed via OAuth with documented scopes.
PressKit
Company-card launcher into the PressKit editor, with publish guardrails and an OAuth install with documented scopes.
TabCalendar
Year-view calendar card in Company and Deal record context, installed via OAuth with documented scopes.
FAQ
Migration service FAQ
Boundary-first answers on scope, billing, and what the deadline means for your cards.