Google is buying software company Apigee for $625 million

Google just announced that it plans to buy Apigee, a once-hot startup that took a dive after its IPO in 2015 but was on the rebound.

Google will acquire Apigee for $17.40 per share in cash, or about $625 million, according to VentureBeat.

Apigee's claim to fame is something called application programming interface (API) tools. APIs allow two software applications to talk each other and share information and have become an increasingly important part of building an app that runs on the cloud.

Apigee was valued at $600 million in the summer of 2014, when it last raised money from private investors. The company was later valued at $494.5 million when it held its IPO, then continued to slide. As of March 2016, Apigee was trading at $7.75 per share - not even half of its IPO price. The company's stock has climbed back up throughout 2016 and is back at IPO-level as of September.

Google's senior vice president Diane Greene wrote in a blog post that Google is buying Apigee because APIs are "vital" for business today.

"The addition of Apigee's API solutions to Google cloud will accelerate our customers' move to supporting their businesses with high quality digital interactions," Greene wrote. "Apigee will make it much easier for the requisite APIs to be implemented and published with excellence."

Apigee's team will join Google following the acquisition, according to the post.