Wayday 2021 - Wayfair’s biggest sale event of the year - brought in a record breaking amount of site traffic and revenue. For some companies, a surge in traffic of this size can mean downtime, lags, or other disruptions.
Yet for Wayfair, these spikes were a non-event. Their longstanding investment in engineering - from cloud migration to hiring - prepared them well for the dramatic growth they experienced in 2021.
To be completely honest, Wayfair engineers had to do very little manual intervention to handle the sudden surge in traffic
In a session for INS1GHTS 2021: Build the Better Future, Alka Sathnur, a Director on the Platform Engineering team at Wayfair, shares how Wayfair has invested in their engineering organization and IT infrastructure over the years.
Learn more about the steps they took to improve network resilience, including:
Proactive, rather than reactive, investments in their IT teams and infrastructure
Migrating infrastructure to the cloud
Implement redundancy through multi-CDN strategy

Proactive Investments in Engineering and IT Teams
From its founding, Wayfair has invested heavily in its engineering organization. Co-founders Niraj Shah and Steve Conine started the company after realizing that consumers were looking for a wider variety of options for any one product - and brick-and-mortar stores simply couldn’t meet that demand.
Their mission across this whole process was very simple, to provide exceptional customer experience to the end user regardless of your location. To achieve this, Wayfair has continuously invested in its engineering organization and in turn has been well positioned to handle significant year-over-year growth. Today, Wayfair’s engineering organization has about 3,500 employees based in research centers across North America.
In her session, Alka also pointed to their partnerships with third party tech providers as a key part of Wayfair’s success. Rather than solely building in-house, Wayfair looks to leading service providers like NS1 for their DNS, cloud, and CDN solutions.
Migrating Infrastructure to the Cloud
When Wayfair experienced unexpected surges in traffic during the initial switch to remote work in 2020 and again during Wayday 2021, their engineering team had to do little manual intervention to keep the site running smoothly. Alka attributes this in part to proactively migrating the entire storefront to the cloud a few years before.
That proactive migration to cloud helped them address three different things:
Ensuring resilience across all storefront components
Reduced OPEX costs
Auto-scaling feature helped them manage dramatic growth easily
However, migrating to the cloud alone won’t provide the level of reliability Wayfair requires. Another key investment is their multi-CDN strategy.
Wayfair: An Engineering Company That Also Happens to Sell Couches
Watch the full session, or check out other sessions like these from INS1GHTS2021 by visiting our replay hub.
Implement Redundancy Through a Multi-CDN Strategy
Wayfair today deploys a dual CDN architecture: one provider to handle all dynamic content, and a second for their static content. They use automated scripts for seamless failover between one CDN to the next.
While half the internet was down, Wayfair sites continued to operate seamlessly.
This strategy has paid off when one of their providers experiences an outage, like the one Fastly experienced in 2021. According to Alka: “while half the internet was down, Wayfair sites continued to operate seamlessly. We were able to seamlessly cutover using our automated scripts from the CDN experiencing issues to our second one, and this allowed for the site performance and the site to stay up with zero downtime for the end user.”
Alka attributes this seamless cutover capability to their NS1 partnership: “Talking a little bit more about our NS1 partnership, DNS or domain name resolution is key to resolving the Wayfair domains.” Wayfair relies on NS1 solutions to steer queries between their CDNs and data centers. Today, NS1 handles about 1.2 billion DNS queries per month for Wayfair.
Learn more about how other leading companies like Wayfair ensure a reliable and high-quality experience for their customers by checking out the following resources: