Staff Software Engineer, Backend

About the role

This role defines the technical direction and operational reliability of Affirm's post-checkout order platform. The team owns core workflows such as orders, captures, refunds, and settlement. Success in this role enables future product capabilities and consistent merchant experiences.

Software engineers turn product ideas into working code. Engineers work in small teams, review each other's work, and ship in small batches. Most teams follow agile practices such as sprints and daily standups. Engineers also write tests, fix bugs, and improve performance. The field values clear communication as much as technical skill. Engineers spend part of every week on planning, code review, and debugging, not just writing new code. The ability to explain a technical decision in plain words separates strong engineers from the rest.

Key facts

What you'll do

Long-term technical strategy is shaped for a one-year horizon and connected to business-critical initiatives. This alignment ensures that engineering efforts support high-impact projects across the organization.

The product development lifecycle is supported through cross-team collaboration with product management, design, and analytics. Such cooperation clarifies technical sustainability, risks, and trade-offs.

Operational ownership is maintained through monitoring, triage rotations, playbooks, policies, testing, and alerting.

These standards are advocated beyond the team through written communication and technical talks.

Talent development is driven by giving feedback and guidance and by modeling example behavior. Such leadership raises the capability of the engineering group.

Requirements

Eight or more years of experience designing, developing, and launching backend systems at scale using languages such as Python or Kotlin are required.

A strong track record of building highly available distributed systems using AWS, MySQL, Spark, and Kubernetes is necessary.

Services are designed with clear API boundaries, strong reliability, thoughtful consistency, idempotency, and failure modes. This focus is especially important in payments, commerce, ledger, or other financially-sensitive domains.

Major features, system components, or deprecations are delivered through a defined technical and execution plan. The produced code is written to be easily understood and used by others.

Comfort with ambiguity is demonstrated when moving from low-level language idioms to the architecture of large systems.

Feedback from engineering and cross-functional peers is gathered and iterated on, showing mastery of input and adaptation.

Effective verbal and written communication enables collaboration with a global engineering team.

Equivalent practical experience or a Bachelor's degree in a related field is required for this position.

Practical notes

This remote-first role is based in the United States, and Affirm may occasionally require work from assigned offices. Role responsibilities align with financial platforms, ledger integrity, and post-checkout commerce infrastructure. Typical interview steps

Hiring for engineering roles usually starts with a recruiter screen, followed by one or two technical rounds. Candidates often solve a coding problem, discuss past projects, and answer system design questions. Some loops include a take-home task. Final rounds typically cover team fit and give candidates a chance to ask questions. Interviewers look for how you break down an unfamiliar problem, not just whether you reach the answer. Practicing a few problems aloud and reviewing your own past projects are the best preparation.

Good to know

Roles in this domain often involve distributed systems concepts such as consistency, idempotency, and failure-mode analysis.

Experience with cloud platforms, container orchestration, and database technologies is common for backend engineers in payments and commerce.

Clear API design and strong reliability practices help services scale and remain understandable over time.

Cross-functional communication is important when working with product, design, and analytics groups.

General engineering leadership includes mentoring peers and contributing to technical standards.