Senior Software Engineer, Backend (Card Acquisition)

Affirm is seeking a Senior Software Engineer to join the Card Acquisition team within the Consumer org. The team plays a critical role in shaping the first experience customers have with Affirm—building trust, clarity, and value from the very first interaction. As a Senior Engineer, you will be responsible for defining long-term technical strategy, mentoring senior engineers, and acting as a force multiplier through your technical depth, operational excellence, and ability to navigate ambiguity. You'll work at the intersection of product, design, and engineering to build polished, performant, and accessible user experiences that directly impact conversion, retention, and business growth.

What You'll Do

• You will be responsible for owning and delivering quarterly goals for your team, leading engineers on your team through ambiguity to solve open-ended problems, and ensuring that everyone is supported throughout delivery.

• You will support peers and stakeholders in the product development lifecycle by collaborating with product management, design, and analytics, participating in ideation, articulating technical constraints, and partnering on decisions that properly consider risks and trade-offs.

• You will proactively identify project, process, technology or business issues, advocate for them, and lead in solving them.

• You take ownership of your team’s operations and availability by ensuring you have the right monitoring, triage rotations, playbooks, policies, testing and alerting in place to support “keep the lights on” & on-call efforts.

• You will foster a culture of quality and ownership by setting or improving code review and design standards for your team, and advocating for them beyond your team through writing and tech talks.

• You will help develop talent on your team by providing feedback and guidance, and leading by example.

• On-Call Rotation - There would be an on-call rotation for this role as a requirement.

What We Look For

• You have 4+ years of experience designing, developing and launching backend systems at scale using languages like Python or Kotlin.

• You have a track record of developing highly available distributed systems using technologies like AWS, MySQL and Kubernetes.

• You have experience defining a technical plan for the delivery of a significant feature or system component with an elegant, simple and extensible design. You write high quality code that is easily understood and used by others.

• You are proficient at making significant changes in a large code base, and have developed a suite of tools and practices that enable you and your team to do so safely.

• Your experience demonstrates that you take ownership of your growth, proactively seeking feedback from your team, your manager, and your stakeholders.

• You have strong verbal and written communication skills that support effective collaboration with our global engineering team.

• This position requires either equivalent practical experience or a Bachelor’s degree in a related field.

Compensation & Benefits

Base Pay Grade - N

ESP base pay range per year: €86,000 - €122,000

Additional benefits include:

• Flexible Spending Wallets for tech, food and lifestyle
• Away Days - wellness days to take off work and recharge
• Learning & Development programs
• Parental benefits
• Employee Resource & Community Groups

We are able to offer visa sponsorship for this role, but do require that someone is based in Spain for the role.