Email Deliverability Specialist

About Customer.io

Over 9,000 companies — from scrappy startups to global brands — use our platform to send billions of emails, push notifications, in-app messages, and SMS every day. Customer.io powers automated communication that people actually want to receive. We help teams send smarter, more relevant messages using real-time behavioral data.

About the role

Hi, my name is Caitlin, Senior Manager, Technical Support at Customer.io, and I'm looking for an Email Deliverability Specialist to join our deliverability program within Technical Support. You'll help customers reach the inbox by diagnosing sending issues, advising on best practices, and guiding senders through an email ecosystem that keeps changing.

You'll be one of several deliverability experts on a team that shares knowledge across Technical Support, so your work reaches well beyond your own queue. You'll partner with Customer Success, Technical Support, and Engineering: taking customer calls, equipping CSMs for customer conversations, working through complex technical cases alongside Engineering, and turning what you see in tickets into documentation, training, and better processes.

You'll thrive here if you think about the health of the whole program, enjoy improving how work gets done, and are equally comfortable digging into a detailed case and having a direct conversation with a customer about acceptable use.

What we value

Empathy and curiosity: You approach every customer with patience and a desire to dig deeper, especially when a conversation gets uncomfortable.

Clarity: You explain complex technical concepts simply and help others do the same.

Collaboration: You build strong partnerships across Support, Customer Success, and Engineering, and you treat customer outcomes as a shared goal.

Thinking at scale: You look at how we do things today and see what could work better for the whole organization, then you help make it happen.

Continuous learning: You stay ahead of evolving standards and see change as a chance to improve how we work.

What you'll do

• Act as a trusted deliverability advisor to customers, handling complex cases through to full resolution and leading customer calls when a conversation needs it
• Audit sender setup and monitor reputation across IPs and domains, using authentication (SPF, DKIM, DMARC) and BIMI, DNS configuration, and provider tools like Google Postmaster Tools, Yahoo Sender Hub, and Microsoft SNDS to diagnose blocklists, spam traps, and engagement drops