What's the hardest production bug you've had to explain to a customer?

Hi everyone, I'm Shashank, founder of TraceX.

We're building TraceX because of one message every engineering team knows: "My refund never arrived." Someone drops what they're doing, queries the database, greps the code, reads last week's deploys, checks the logs, and an afternoon later finds the cause. In our demo it's a migration that renamed a state a background worker still filtered on.

TraceX does that investigation for you, read-only against your database, code and logs. It shows the evidence for every claim (and the hypotheses it ruled out), opens the fix as a pull request, and drafts the reply to the customer.

Before we launch, I'd love to hear from you:

1. What's the hardest "why did this happen to this customer?" bug you've had to track down?

2. What would you need to see before letting an AI tool read your production systems?

There's a sandbox you can try without signing up: https://app.tracexpro.com/sandbox

Every answer will shape what we build next. Thank you!