What caused the sudden 30% increase in transaction failures for Juspay's UPI payments service last week?

Introduction

The sudden 30% increase in transaction failures for Juspay's UPI payments service last week is a critical issue that demands immediate attention and thorough analysis. As we delve into this problem, we'll employ a systematic approach to identify, validate, and address the root cause while considering both short-term fixes and long-term strategic implications.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking this could be related to a recent system update. Has there been any significant changes to the UPI payment infrastructure in the past week?

Why it matters: System updates often introduce unforeseen issues. Expected answer: Yes, a minor update was rolled out. Impact on approach: If confirmed, we'd focus on rollback options and code review.

• Considering user segments, I'm wondering if this is affecting all users equally. Are we seeing any patterns in terms of user demographics or transaction types most impacted?

Why it matters: Helps narrow down potential causes and prioritize fixes. Expected answer: Higher failure rates among first-time users or specific transaction types. Impact on approach: Would guide us to investigate onboarding processes or specific payment flows.

• Given the scale of the issue, I'm curious about any changes in external factors. Have there been any significant shifts in network infrastructure or banking system integrations?

Why it matters: External dependencies can significantly impact payment systems. Expected answer: No major external changes reported. Impact on approach: If confirmed, we'd focus more on internal systems and processes.

• Thinking about data integrity, I'm concerned about potential changes in measurement systems. Has there been any modification to how we track or define transaction failures?

Why it matters: Ensures we're dealing with a real issue, not a reporting anomaly. Expected answer: No changes to measurement systems. Impact on approach: If changes occurred, we'd need to audit our tracking systems first.