Cumulus Networks co-founder and former CTO JR Rivers is joining Amazon Web Services, according to a source with knowledge of the hire.

Rivers left the open networking company three months ago and started “looking for [his] next challenge,” according to his Linkedin profile.

AWS’ next challenge, on the other hand, is well documented. The cloud giant is moving into the enterprise data center with Outposts, its on-premises hardware that will offer configurable compute and storage in customers’ private data centers. It will also connect on-premises environments to AWS’ services in the public cloud. The company has said Outposts will be available by the end of the year.

While SDxCentral can’t confirm what River’s new role will be at Amazon, it’s a safe bet that River’s will land in an executive leadership role — and that his background will be a boon to AWS as it pushes into data center networking.

Rivers served as Cumulus’ founding CEO from January 2010 until March 2016, when Rivers announced that Josh Leslie would succeed him as CEO and Rivers would take the role of CTO.

The company is best known for its Linux network operating system, which runs on more than 30 hardware platforms from a dozen vendors including Dell EMC, Hewlett Packard Enterprise, Mellanox, and Lenovo.

Earlier this year it partnered with Nutanix on an integrated product that combines Nutanix’s hyperconverged infrastructure stack with Cumulus’ open networking software.

And in March, Cumulus Linux became the first network operating system to support Facebook’s Minipack, which Facebook contributed to the Open Compute Project (OCP).

Cumulus has long been active in OCP and has championed open networking since its founding.

As AWS prepares to roll out its on-premises hardware, several networking companies have been angling for a piece of the data center play. This includes Rivers’ former employer, Cisco, whose CEO Chuck Robbins said Outposts presents an opportunity for the networking giant.

Robbins, speaking at the Goldman Sachs Technology and Internet Conference, said he didn’t want to imply that a deal with AWS was in the works. But he added that AWS Outposts with Cisco networking was “certainly conceivable.”

Last month Big Switch Networks also said its networking products are “ideally suited” for cloud providers’ on-premises plays such as Amazon Web Services (AWS) Outposts.