After nearly five years at the helm of Yahoo, Marissa Mayer is bidding an optimistic farewell to her company.

Mayer, who became CEO of Yahoo in 2012, posted on Tumblr a copy of an email she sent employees Tuesday as Verizon completed its $4.5 billion acquisition of the one-time internet giant’s operations. As previously planned, Mayer announced her resignation “given the inherent changes to my role.”

“While reaching this moment has certainly been a long road traveled, it marks the end of an era for Yahoo, as well as the beginning of a new chapter —it’s an emotional time for all of us,” she wrote in the email titled “Nostalgia, Gratitude, and Optimism.” “Looking back on my time at Yahoo, we have confronted seemingly insurmountable business challenges, along…