[Haskell-cafe] The instability of Haskell libraries

Don Stewart dons at galois.com
Fri Apr 23 17:29:54 EDT 2010

> Don Stewart wrote:
>> I'll just quickly mention one factor that contributes:
>>     * In 2.5 years we've gone from 10 libraries on Hackage to 2023 (literally!)
>> That is a massive API to try to manage, hence the continuing move to
>> focus on automated QA on Hackage, and automated tools -- no one wants
>> to have to resolve those dependencies by hand.
> Yep, it's massive, and it's exciting.  We seem to have gone from stodgy  
> old language to scrappy hot one.  Which isn't a bad thing at all.
> Out of those 2023, there are certain libraries where small changes  
> impact a lot of people (say base, time, etc.)  I certainly don't expect  
> all 2023 to be held to the same standard as base and time.  We certainly  
> need to have room in the community for libraries that change rapidly too.
> I'd propose a very rough measuring stick: anything in the platform ought  
> to be carefully considered for introducing incompatibilities.  Other  
> commonly-used libraries, such as HaXML and HDBC, perhaps should fit in  
> that criteria as well.

Oh, the Platform has very strict standards about APIs,

When a package may be added:    


and once it is in, only non-API changing bug fixes are during a minor
series (12 month release cycle). On 12 month (major) releases, packages
may modify their API under the current standard.

We just haven't been around long enough to have much of an effect. 
The 2..5 year plan is that significant new stability is reintroduced via
the HP.

-- Don

More information about the Haskell-Cafe mailing list