Your integration didn't break. It just stopped being told anything.
Every connected system runs on someone else's API, and vendors retire old versions on their own calendar, not yours. When that date passes, nothing crashes - data just quietly stops moving, until someone notices weeks later.
No crash, no red banner - just a connection that stopped being told anything
On December 4, 2026, HubSpot permanently turns off the original version of its Pipelines API - any integration still calling it simply stops getting a response. Pipedrive retired a batch of its own v1 endpoints, including Deals and Activities, on January 1. Google's Content API for Shopping went dark on August 18. None of this shows up as a bug in anyone's code. A form that used to create a deal now creates nothing. An order that used to sync into fulfillment just... doesn't. The business didn't do anything wrong. It just didn't read a changelog post a vendor published months earlier.
The outage you don't notice costs more than the one you do
One SaaS platform's undocumented payment API deprecation caused a week-long outage that cost it $200,000 in lost revenue before anyone traced the cause. That's the expensive version. The quiet version is worse in a different way: nobody declares an incident, because nothing looks broken. A report is just missing a week of rows. A customer calls asking where their invoice is. The business spends days treating it like a one-off mistake before realizing the pipe itself stopped running.
Someone owns the connection, until they don't
Maintaining a single integration already runs a business $50,000 to $150,000 a year once you count the engineering time to keep it working, and most companies have more than one. The accounts that get hit hardest are the ones where the integration was set up once by someone who's since moved on or moved to a different project, and the vendor's deprecation email went to an inbox nobody's checked since. The notice wasn't hidden. Nobody was assigned to read it.
The ACS approach
We treat every third-party connection like it has an expiration date, because it does - someone else's, not ours. That means knowing which systems depend on which APIs, who's actually subscribed to each vendor's changelog, and building integrations so a version bump breaks loud and early in a test environment, not quiet and late in production. An integration is worth building only if someone is still watching it a year after launch.