Senior Backend Engineer — Test Platforms (Remote)

Affirm; Spain (TX); Hybrid; USD 104,000 - 150,000; Full time

Benefits offered by this job

Health coverage and benefits

Flexible Spending Wallets

Time off and wellness days

Employee stock purchase plan

Job summary

Affirm is seeking a Senior Software Engineer, Backend (Test Enablers) to join the Test Platform Engineering team. The role focuses on building platforms for synthetic identities, test data seeding, mocking, and deterministic validation workflows, enabling faster, safer validation and scalable CI signals.

As part of our remote Spain team, you will mentor engineers, lead medium-to-large projects, and help scale our testing infrastructure to support AI-assisted development while maintaining

Qualifications

• 5+ years of software engineering experience.
• Strong backend experience with Python, Kotlin, or Java.
• Experience designing distributed systems and testing infrastructure.
• Ability to drive ambiguous technical work to completion.

Responsibilities

• Design, build, and maintain scalable backend systems for synthetic identities, test data seeding, and load testing.
• Evolve testing strategy toward scalable, component- and integration-focused testing.
• Build platform capabilities for safe, repeatable load testing and observability.
• Improve reliability, observability, and adoption of test platforms across teams.
• Lead medium-to-large technical projects from definition to rollout and ownership.
• Mentor engineers and contribute to RFCs, ADRs, and architecture discussions.
• Write high-quality, maintainable code.

Skills

5+ years

Backend engineering

Python

Kotlin

Java

Distributed systems

Ownership

Async communication

Tools

CI/CD platforms

Test automation frameworks

Mocking tools

Job description

Affirm is seeking a Senior Software Engineer, Backend (Test Enablers) to join the Test Platform Engineering team. The role focuses on building platforms for synthetic identities, test data seeding, mocking, and deterministic validation workflows, enabling faster, safer validation and scalable CI signals.

As part of our remote Spain team, you will mentor engineers, lead medium-to-large projects, and help scale our testing infrastructure to support AI-assisted development while maintaining