One thing that isn't called out is cost to your clients.
Last week I was fixing a bug caused by vendor who had updated an API in an incompatible way (probably via a shim of some sort) this was causing our shared ultimate end customer to be at risk of regulatory fines. Thankfully as it turns out the last 1.xx version of the API was mostly adding functionality we don't use and we can swap to using a new field without lots of pain.
However this does mean we need to spend a couple of weeks of developer and tester time retesting the interface code. Cost I would guess $10,000 by the time we add in all the PM/PO/DevOps time multiply that by a few customers and it adds up fairly quickly.
Moving to version 2.xx doesn't look too bad but the monolithic protobuf file has been split into parts and the upgrade is probably going to take a 6-8 weeks as they've also changed some of the enum values and properly deprecated stuff. My gut feel from having spent a couple of hours looking at V2.xx is it mostly compatible but this vendor has form for hiding a surprise change (they changed from representing money as an int with an implied decimal place to a long+int)
Again probably not too much work overall but it will cost $20,000 to swap versions and the opportunity cost of not doing something else instead.
We have the same problem with the API for external applications we provide. We know folks are running very elderly versions (over 3 years old) and our next version is huge change for client applications. We've taken advantage of this change to rename a load of stuff and explicitly add types in various places. I doubt we'll be able to sunset the old API for many years.
Last week I was fixing a bug caused by vendor who had updated an API in an incompatible way (probably via a shim of some sort) this was causing our shared ultimate end customer to be at risk of regulatory fines. Thankfully as it turns out the last 1.xx version of the API was mostly adding functionality we don't use and we can swap to using a new field without lots of pain.
However this does mean we need to spend a couple of weeks of developer and tester time retesting the interface code. Cost I would guess $10,000 by the time we add in all the PM/PO/DevOps time multiply that by a few customers and it adds up fairly quickly.
Moving to version 2.xx doesn't look too bad but the monolithic protobuf file has been split into parts and the upgrade is probably going to take a 6-8 weeks as they've also changed some of the enum values and properly deprecated stuff. My gut feel from having spent a couple of hours looking at V2.xx is it mostly compatible but this vendor has form for hiding a surprise change (they changed from representing money as an int with an implied decimal place to a long+int)
Again probably not too much work overall but it will cost $20,000 to swap versions and the opportunity cost of not doing something else instead.
We have the same problem with the API for external applications we provide. We know folks are running very elderly versions (over 3 years old) and our next version is huge change for client applications. We've taken advantage of this change to rename a load of stuff and explicitly add types in various places. I doubt we'll be able to sunset the old API for many years.