Remote Senior Backend Engineer - Real-Time Fraud Platform

Affirm; Spain; Remote; EUR 70,000 - 110,000; Full time

Benefits offered by this job

Flexible Spending Wallets for tech,食品,

Away days—wellness days

Employee Resource & Community Groups

Health care coverage

Flexible Spending Wallets

Time off

ESPP

Job summary

Affirm is hiring a Senior Software Engineer to build the backend for fraud decisioning across markets. Remote Spain.

You will own real-time services in Python or Kotlin, integrate vendors, and scale launches across regions, collaborating with Product, ML, Fraud Ops, and other Fraud Engineering teams. The role emphasizes ownership, code quality, on-call duties, and the global reach of the Fraud International Team.

Qualifications

• 5+ years building backend systems at scale with Python or Kotlin.
• Experience with distributed systems and cloud infra (AWS, Kubernetes).
• Strong system design skills and maintainable services.
• Familiar with AI-assisted coding and review processes.
• Proficiency in SQL and data-rich environments.
• Experience with CI/CD and safe deployments.
• Excellent written and verbal communication in distributed teams.
• Experience scaling for multiple markets or regions (nice to have).

Responsibilities

• Own quarterly goals and deliver for your team.
• Design and implement real-time fraud decisioning services.
• Evolve platform to launch in new markets quickly.
• Integrate region-specific vendors and ML signals.
• Maintain on-call readiness and system reliability.
• Mentor teammates and uphold code quality.

Skills

Python

Kotlin

Distributed systems

SQL

CI/CD

AI tooling

Communication

Ownership

Tools

AWS

Kubernetes

Snowflake

dbt

Airflow

Chronosphere

Claude Code

Job description

Affirm is hiring a Senior Software Engineer to build the backend for fraud decisioning across markets. Remote Spain.

You will own real-time services in Python or Kotlin, integrate vendors, and scale launches across regions, collaborating with Product, ML, Fraud Ops, and other Fraud Engineering teams. The role emphasizes ownership, code quality, on-call duties, and the global reach of the Fraud International Team.