Have you ever felt like searching through tweets you published years ago? Now you can using Twitter's search engine. Searches on the social network were previously limited to just a week before tweets were removed from the index (but still viewable by other means - direct links, profile timelines, etc). Twitter has worked on rolling out a new search engine that not only keeps up with the plethora of tweets being beamed to the service on a daily basis, but also enable users to search through those vintage messages.
"Our search engine excelled at surfacing breaking news and events in real time, and our search index infrastructure reflected this strong emphasis on recency. But our long-standing goal has been to let people search through every Tweet ever published."
For the time being the Twitter search is restricted by just a few keyword terms, but the company aims to improve the experience by adding more complex queries. It was generally the case for Twitter to stand back and allow third-party developers to swoop in with more advanced functionality, but the company and its rather small team of engineers have been soldiering on to offer a native experience, one that's available both on the web and on official mobile apps.
When one considers the scope of the project, it's quite the achievement. The team needed to find a way to merge the index with literally millions of new entries each and every second. Also, SSDs are now used for storage over saving tweets in main memory for speedy, and more expensive access. Give it a try yourself the next time you visit Twitter.com or fire up one of the official apps (currently works on iOS and Android).
Also, check out the full blog post by Search Infrastructure Engineer Yi Zhuang for more details.