Customer.io Advanced Troubleshooting

Overview

Advanced debugging techniques for complex Customer.io issues: systematic investigation framework, API debug client, user profile analysis, campaign/broadcast debugging, network diagnostics, and incident response runbooks.

Prerequisites

• Access to Customer.io dashboard (admin recommended)
• Application logs access
• curl for API testing

Troubleshooting Framework

For every issue, answer these five questions first:

1. What is the expected vs actual behavior?
2. When did the issue start? (Check deploy history, CIO status page)
3. Who is affected — one user, a segment, or everyone?
4. Where in the pipeline — API call, delivery, or rendering?