Senior Software Engineer, Backend (ML Training and Serving)

Affirm, Inc.; United States; Remote; USD 120,000 - 180,000; Full time

Benefits offered by this job

Health coverage

Monthly technology stipend

Wellness stipend

Flexible time off

Holidays

Employee stock purchase plan

Remote work (Canada)

Job summary

Affirm, Inc. seeks an experienced backend engineer to build and operate shared infrastructure for training and serving machine learning models in production.

The role blends backend engineering, distributed systems, and ML platform development to deliver dependable services that accelerate model delivery. You will own team goals, mentor engineers, and collaborate with product, design, and analytics to address constraints and risks.

Qualifications

• 4+ years designing, building, launching backend systems at scale.
• Experience with Python or Kotlin in production.
• Experience with highly available distributed systems and cloud infra.
• Strong written and verbal communication for distributed teams.
• Ownership mindset and willingness to seek feedback.

Responsibilities

• Own team goals and guide engineers through technical work.
• Collaborate with product, design, and analytics on constraints, risks and decisions.
• Identify and lead efforts to address technical or operational problems.
• Monitor service health and contribute to incident response.
• Set and improve code review and design practices; mentor others.

Skills

Python

Kotlin

Distributed systems

Backend design

Communication

Tools

Cloud infrastructure

Container platforms

Databases

Job description

Role overview

Build and operate shared infrastructure for training and serving machine learning models in production. The work combines backend engineering, distributed systems, and ML platform development, with a focus on dependable services that help other teams deliver models and improve their development pace.

Responsibilities

• Own team goals and guide engineers through open-ended technical work and delivery.
• Collaborate with product, design, and analytics partners on ideas, constraints, risks, and implementation decisions.
• Identify and lead efforts to address technical, operational, process, or business problems.
• Monitor service health and availability using metrics, and contribute to incident response and on-call work.
• Set and improve code review and design practices; share technical guidance through writing and talks.
• Support colleagues' development with feedback, mentorship, and strong engineering examples.

Requirements

• Four or more years designing, building, and launching backend systems at scale, using languages such as Python or Kotlin.
• Experience developing highly available distributed systems, including work with cloud infrastructure, databases, and container platforms.
• Ability to plan delivery of a significant feature or system component with a clear, extensible design.
• Experience making substantial changes safely in a large codebase, supported by effective engineering tools and practices.
• Strong written and verbal communication for collaboration with a distributed engineering team.
• Demonstrated ownership of professional growth and willingness to seek feedback.

Nice to have

• Experience training and deploying machine learning models in production.

Benefits and work setup

• Remote work is available to candidates residing in specified Canadian provinces.
• Health coverage for employees and dependents
• Monthly technology and wellness stipends
• Flexible time off
• Holidays
• An employee stock purchase plan