It doesn’t really matter if Twitter’s Chief Architect Blaine Cook was fired or resigned. The important thing is that he’s gone now, and this gives Twitter the opportunity to hire someone (or a team) who may actually be able to scale the nearly two year old service and keep it live.
Cook was directly responsible for scaling Twitter, and he very much failed in his job. A year ago he spoke at the Silicon Valley Ruby Conference about scaling Rails applications. His presentation suggested Twitter’s problems were behind them, but in fact some of their biggest stumbles hadn’t occurred yet. Note in particular slide 9 of that presentation, where Cook says about scaling Rails apps like Twitter: “It’s Easy. Really.” Whether Twitter’s woes were all on Cook’s shoulders or not, he should not have been boasting about solving the problem last year.
Meanwhile, Twitter has made at least three key hires this year on the technical side. Lee Mighdoll joined as VP Engineering and Operations in January. And this week they hired two scaling experts – John Kalucki and Steve Jenson (“known for his work scaling Blogger and Blogspot”).