Incident Response & Post-Mortem: Restoring Confidence After Production Failure

Context

A consolidated frontend release introduced a regression affecting the Logbook feature—a critical workflow for restaurant operations. Routes that previously worked began returning 404 errors, blocking users from accessing saved logbook entries.

The incident occurred immediately after a high-visibility architectural milestone: unifying multiple micro-frontends into a single consolidated application. The timing created pressure to either rollback the entire release or diagnose and fix the issue quickly.

The Problem

Users reported broken routing in production. The scope of impact was unclear: was it isolated to Logbook, or were other features affected? Was this a regression in the new consolidated code, or an unrelated issue that happened to surface after deployment?

The engineering team and product stakeholders needed answers quickly. Rolling back would undo weeks of architectural work. Proceeding without understanding the issue risked compounding the problem or masking its root cause.

Immediate Response

Rather than assuming, we diagnosed systematically.

Within 45 minutes of the initial report, root cause was identified: URL handling in the consolidated codebase was using direct href mutation instead of history-based routing. This broke the expected /r/ routing behavior that the frontend relied on.

The investigation didn't stop at the first affected route. We identified and catalogued all affected paths, preventing the risk of a partial fix that would leave other broken routes in production.

A fix was implemented using history-based routing to restore expected behavior, and the PR was ready for validation.

Throughout, communication remained clear and frequent. Updates were posted in public channels so QA, support, and product stakeholders could follow progress. This maintained confidence that the issue was being addressed methodically rather than thrashed on.

Beyond the Fix: Post-Mortem Process

Once the immediate crisis was resolved, we chose not to move on. Instead, a post-mortem was scheduled despite no formal requirement to hold one.

This decision was deliberate: incidents are opportunities to learn, and learning requires structured reflection. The post-mortem wasn't about blame—it was about understanding systemic gaps that allowed this class of bug to reach production.

The investigation identified three categories of gaps:

Testing Gaps: The affected routes had limited test coverage. New routing behavior introduced during consolidation wasn't validated against existing route contracts.

Observability Gaps: Sentry was configured across multiple legacy boundaries without consolidation. Error signals were fragmented across separate instances, reducing visibility into widespread issues.

Process Gaps: QA validation required explicit sign-off before production deployment, but the escalation path and validation criteria weren't clearly formalized.

Impact

The incident was resolved in approximately 1.5 hours from report to staged deployment. Production routing was restored without rollback.

The post-mortem produced follow-up work that addressed root causes rather than symptoms: test coverage was expanded for routing, Sentry consolidation was prioritized, and deployment gating processes were formalized.

Most importantly, the response demonstrated a commitment to learning. The team didn't treat the incident as an isolated fire to extinguish; it was treated as data about how the system fails and what needs to improve.

Reflection

Incidents are inevitable. How organizations respond to them determines whether they become learning opportunities or sources of blame and burnout.

By approaching the response systematically—diagnosing thoroughly rather than guessing, communicating clearly, and following up with structured reflection—we transformed a crisis into evidence for what the system needs to improve.

This work reinforces that operational excellence isn't about preventing all failures—it's about responding to failures in ways that build confidence and resilience over time.