Senior Software Engineer, Back-end (Fraud) at Affirm

✨ The Stack take on this Affirm job

• 🏢 Affirm has 38 jobs here, 25 with visa sponsorship see all
• 🛂 Visa: Highly Qualified Professional permit. Education: Higher education degree guide
• 💡 No salary shown. Ask Affirm if it is above the minimum.

Updated 2026-11-05, from our data and official sources.

Apply with your AI assistant

With The Stack connected to Claude, ChatGPT or Cursor, paste this. Your assistant tailors your CV and cover letter, checks the visa facts and gives you the apply link.

Help me apply to this job on The Stack: https://jobs.trythestack.co/jobs/senior-software-engineer-back-end-fraud-affirm

Not connected yet? Connect in a minute. To help your user apply, call the MCP tool prepare_application with slug "senior-software-engineer-back-end-fraud-affirm": it returns the apply link, the visa facts and a CV and cover letter checklist. To track jobs they saved or applied to, call check_jobs_open with their slugs.

About the role

Responsibilities:
- Own and deliver quarterly team goals; lead engineers through ambiguity to completion.
- Design and implement real-time fraud decisioning services and APIs using Python or Kotlin.
- Build platform and tooling to standardize market launches (rules, models, vendor configs) for new countries.
- Integrate region-specific fraud and risk vendors and operationalize ML/AI signals in decisioning flows.
- Maintain system reliability: monitoring, alerting, on-call rotations, and incident response.
- Collaborate cross-functionally with Product, Compliance, ML, Fraud Operations, and Fraud Strategy.

Requirements:
- 5+ years building backend, distributed services using Python or Kotlin.
- Strong experience with AWS, Kubernetes, and relational databases (MySQL/Postgres) and SQL.
- Proven track record designing APIs, scalable decisioning systems, and CI/CD pipelines.
- Familiarity with fraud prevention, risk systems, vendor integrations, and ML-driven features.
- Good communication skills for cross-region collaboration and stakeholder alignment.
- Comfortable working remotely in Europe and participating in on-call rotations.

Responsibilities

Design and implement real-time fraud decisioning services and APIs to extend Affirm's fraud systems into international markets. Lead engineers through ambiguity to deliver quarterly goals and maintain system availability through monitoring and on-call rotations.

Requirements

Requires 5+ years of experience in backend systems using Python or Kotlin, with proficiency in AWS, Kubernetes, and SQL. Candidates must be skilled in AI-driven engineering and have a strong track record of delivering maintainable distributed services.

Key skills

• Python — in 1200 other listings on The Stack
• Kotlin — in 251 other listings on The Stack
• AWS — in 802 other listings on The Stack
• MySQL — in 93 other listings on The Stack
• PostgreSQL — in 296 other listings on The Stack
• Kubernetes — in 585 other listings on The Stack
• System Design — in 199 other listings on The Stack
• SQL — in 545 other listings on The Stack
• CI/CD
• AI-driven Engineering
• Distributed Systems
• Backend Development

On The Stack (as of 2026-11-05)

• Affirm has 37 other listings on The Stack, 24 of them marked as offering visa sponsorship.
• 76 visa-sponsored jobs in Spain on The Stack, posted in the last 60 days.
• 195 visa-sponsored software engineer jobs in Europe on The Stack, posted in the last 60 days.

Frequently asked questions about Affirm

Is this Senior Software Engineer, Back-end (Fraud) role still open?

It was posted on 2026-07-20. Listings more than 30 days old may no longer be active, so check Affirm's site before applying.

Does Affirm offer visa sponsorship?

This listing is marked as offering visa sponsorship. Eligibility rules are set by the employer, so check the details on Affirm's site.

Where is this role located?

The listing gives the location as Spain. It is marked remote.

What skills does this role ask for?

The listing names: Python, Kotlin, AWS, MySQL, PostgreSQL, Kubernetes, System Design, SQL, CI/CD, AI-driven Engineering, Distributed Systems, Backend Development.