I completely disagree (with the article) when it comes to startup staffing. There are a few cases where having a domain expert is necessary (e.g. if you're writing, say, a new database system or doing realtime software, or if you're selling into a specific market where connections are necessary) but for most startups you're way better off having someone who's a decent programmer but also a competent sysadmin, pretty good with customers, or decent contract negotiator. An early stage startup probably won't even know what to specialize _in_.

Better yet is having someone who's a fast learner and can pick any/all of the above up as needed.