APIs Are Forever, Wait No...They Can Go Away at Any Time

This makes me think of the not-so-recent deprecation of Offline Access by Facebook. I do not know whether it will be supported ad infinitum, but if not, it requires other completely-functional apps to be majorly rearchitected or break entirely.<p>There is rarely a good reason to actively destroy old API - section it off, keep it out of new code, maybe even kill the documentation so new developers don't use it, but it's bad business and downright disrespectful to the third-party developers who enrich your platform.

as I have tried to start a business building on top of API's, this is in general a risky business. Not only can they disappear, but also work incorrectly, go down, change overnight without notification. Also your access can be shut down just because of a change of heart on their side<p>If you don't pay for access and have some kind of contract (Twitter firehose, Bing API), yes your business goals are not aligned and you'd better prepare for the worse.

Clear deprecation policies are great, but I also think that every public API needs to be explicitly versioned. This is commonly achieved by including the version in the URL (api.example.com/v3/whatever), but a suitable header (API-Version: 20120420) would also work.<p>Once published, a specific version of an API should never change in a backward-incompatible way, only become superseded by newer versions. Likewise, you don't change or deprecate individual methods, you merely stop supporting older versions. That would make it much easier for developers to keep track of API changes.

This is one of the best arguments for scraping data, if you can manage it. Generally businesses invest much more time and resources into maintaining an up-to-date, usable website than they would on an API, especially if they don't use a service-oriented architecture internally (ie, consume their own API)

Programmable Web noticed this last year when Google started charging more for their older APIs. Why kill the API when you can make as much money as you want from its users?<p>&#62; Google is also providing developers a reason to finally move their maps off of Google Maps V2. Overages for the old version of Google Maps costs $10 per 1,000 map views.<p><a href="http://blog.programmableweb.com/2011/10/27/google-maps-usage-fees-how-many-developers-will-have-to-pay/" rel="nofollow">http://blog.programmableweb.com/2011/10/27/google-maps-usage...</a>

How does one build a software that will not deteriorate over time, if he uses unstable API?. I don't know. Just don't use unstable API if you don't have to.