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Affirm

Mid

Build the core issuing and transaction-processing systems behind every Affirm Card swipe

Affirm's Consumer Engineering team owns the issuing and processing infrastructure that sits on the critical path of every Affirm Card transaction — authorization, transaction processing, account/card lifecycle, tokenization, and platform security. This interview probes whether a 1.5+ year backend engineer can design, ship, and operate systems at that scale with Python or Kotlin, AWS, MySQL, and Kubernetes.

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What this interview tests

  • Backend system design for authorization/transaction processing
  • Python or Kotlin proficiency
  • Distributed systems fundamentals (AWS, MySQL, Kubernetes)
  • Production debugging in a large codebase
  • On-call/operational ownership and metrics

Common question themes

Design a piece of the card authorization or transaction pipeline

Break down a business requirement into a phased technical plan

Debug an unfamiliar service during an incident

Give code review feedback on someone else's PR

Describe an on-call escalation and how you resolved it

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