[mgliwka]

A good additional measure is a scheduled brownout. Turn off the API for a couple of hours or a day to make the consumers notice, then turn it back on for some weeks to give them time to migrate.

Google did this with their old Helm chart repository.

[ozim]

Then you might find some cases, where an API endpoint is called once a month o once a year but it is critical, that will bite you back really hard.

[vegetablepotpie]

One solution I’ve seen posted here (can’t remember the link) is to put a sleep in some call and step it up every day/week/month until retirement.

That way when the application slows down, people complain, a story is created to figure out why, and the answer will be the library is deprecated and needs to be migrated.

The calls can always be made, they just get more expensive.

[michaelt]

Naturally, you would combine any planned API delay or outage with conventional deprecation steps like updating documentation well in advance, posting to your blog, twitter and mailing list, e-mailing every identifiable user of the deprecated API, and having your account managers reach out to paying customers who use the API.