Once you get to the scale of "all programming" perhaps there is not so much shared culture or knowledge to bind a single community together. This might be relat

Once you get to the scale of "all programming" perhaps there is not so much shared culture or knowledge to bind a single community together. This might be related to the way communities of practice organise at different scales, rather than something specific about programming. (Compare: Why is there no real on-line piano-playing community?) A related question is: why are developer communities balkanized by programming language, application domain, programming paradigm, educational background? In part this is tribalism. Often corporations take advantage of this tendency to gain market advantage, which amplifies the effect. Finally, why should there be a single, unified, online community? There are many online communities of programmers and that seems to be working pretty well.