Bringing Professionals Closer to Their Dream Job with Transactional Email

Written by Mailgun Team

Categories: Case Studies

3 minute read time

Case Study:Quantum Response Network

For a global job site like Quantum Response Network, sustaining high email throughput and
generating return traffic to their websites is an important measure of success and profitability. With
over one million active users in key markets such as the UK, the US, Canada, Australia, South Africa,
India, Singapore, and the United Arab Emirates, Quantum Response Network needed a reliable Email
Service Provider (ESP) to partner with and grow their business. To gain market share in the Online
Recruitment space, Quantum Response Network was looking for the right infrastructure fit that could
process and send over 1.2 million daily marketing emails around the clock.


Quantum Response Network needed to scale their infrastructure capabilities as their business
grew year-over-year. While their daily sending volume continued to increase, their previous
partner could not keep up with the incremental growth. They wanted to be proactive and
understand what they could do better on their side to mitigate volume-related issues. The goal
was to reach sending capacity of 1.5 million daily emails, and it wasn’t something they could do if
they stuck to the same sending infrastructure.

Quantum Response Network had a simple sending infrastructure that would run email activity
through 3 different top-level domains: each with at least 6 subdomains that had different mailing
streams. It was barely enough to balance the heavy load of transactional emails sent to welcome
subscribers and send them daily marketing emails. That’s when they decided to evaluate other ESP
options, and they narrowed down the search to Mailgun, Mailjet, and SendGrid.

“Our previous partner was having serious issues coping with the volume of emails that we send out each day. We also felt that we didn’t have a clear idea of where we stood with our deliverability.”
Graham Everitt, Director
Quantum Response Network


With help from Mailgun, Quantum Response Network developed an infrastructure strategy that
would provide higher visibility into email delivery. They began to build their sending reputation
gradually using dedicated IPs tied to their domains, and balanced the load using shared IP
resources to send over 1.2 million emails per day. Quantum Response Network integrated the
Mailgun email API and made improvements to their infrastructure, working with a dedicated
Technical Account Manager to maximize deliverability performance.

“…we found that Mailgun’s API could cope with any volume that we could throw at it. What was taking our previous partner 29 hours to send took Mailgun fewer than 2 hours.”

Through separation and aggregation of over and underperforming mail streams, they found that
Quantum Response Network was able to send email faster than their system could generate
transactional email. Mailgun provided the email know-how and best practices that Quantum
Response Network used to solve for the high-volume constraints they had experienced before.


By using Mailgun’s shared IP resources, Quantum Response Network was able to lift the email
sending performance of their key subdomains, and use best practices to sustain improved
performance and deliverability. They can now measure and manage the impact of email delivery
on their business. As a result, Quantum Response Network experienced a 95% increase in email
sessions that have led to recurring web traffic to their page, and 1350% increase in sending speed
for transactional email messages.


“Deliverability doesn’t need to be a silent killer, though it was to us previously…this doesn’t mean we feel that we have perfect deliverability as there isn’t such a thing, but we feel that by working alongside Mailgun we have the ex-pertise required to manage it as well as is possible.”

About Mailgun

A Y-Combinator success story, Mailgun is an email delivery engine created by developers for
developers. Since 2010, Mailgun has provided deliverability expertise and leading technology
via cloud-based email APIs for customers such as Slack, Github, and Shopify. Through its own
proprietary technology, Mailgun strives to continuously ensure you can send, receive, and track
email effortlessly.
About Mailgun

Download Case Study

Modified on: February 21, 2019

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