Senior Software Engineer, Backend (Post-Purchase International)

Affirm; Polska; Hybrid; PLN 180,000 - 300,000; Full time

Benefits offered by this job

Equity

Private healthcare

Remote-first

Learning & development

Job summary

Affim is seeking a Senior Software Engineer, Backend (Post-Purchase International) to own backend systems and help launch across international markets. You will collaborate with European engineering counterparts to build scalable, reliable post-purchase experiences.

You’ll design and ship services in Python or Kotlin, work with AWS, MySQL, and Kubernetes, and may contribute to frontend work. This is a remote-first role based in Poland with equity and benefits.

Qualifications

• 4+ years of experience designing, developing and launching backend systems at scale.

Responsibilities

• Own and deliver quarterly goals for the backend team.
• Collaborate with product management, design & analytics; articulate constraints and trade-offs.
• Identify and lead resolution of project, process, or tech issues.
• Support operations and on-call efforts; monitor metrics and keep services reliable.
• Set or improve code reviews and design standards; write clear, maintainable code.
• Occasionally contribute to full-stack development and front-end components.

Skills

Python

Kotlin

AWS

MySQL

Kubernetes

React or Vue (frontend optional)

Tools

AWS

Job description

Senior Software Engineer, Backend (Post-Purchase International)

Remote Poland

At Affim, we exist for the moments that matter—giving people a clear, predictable way to pay over time, with no hidden fees, no surprises, and no tradeoffs on what matters most.

Join the pioneering Post-Purchase International team at the forefront of Affim’s global expansion. You’ll help build the foundational platform and customer experiences needed to bring Affim’s products to a new generation of international markets. The team owns and evolves the end-to-end post-purchase journey across international markets, ensuring that customers can confidently manage their purchases and access experiences tailored to their local needs. Success requires deep collaboration: you’ll partner closely with European engineering counterparts and teams across Affim’s global Post-Purchase organization to develop cohesive, scalable solutions. If you’re passionate about creating world-class customer experiences and excited by the challenge of launching products in new regions, join us. Help shape the next generation of Affim’s post-purchase platform and define our presence around the world.

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 your peers and stakeholders in the product development lifecycle by collaborating with product management, design & analytics by 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 will support the operations and availability of your team’s artifacts by creating and monitoring metrics, escalating when needed, and supporting “keep the lights on” & on-call efforts.
• You will foster a culture of quality and ownership on your team by setting or improving code review and design standards for your team, and advocating for them beyond your team through your writing and tech talks.
• You will occasionally contribute to full-stack development, including working on front-end components to help deliver end-to-end features.
• You will help develop talent on your team by providing feedback and guidance, and leading by example.

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 are enthusiastic about occasionally working on front-end code (no prior front-end experience is required).
• 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.

What would be a bonus

• You’ve had exposure to building web apps with declarative UI frameworks (e.g., React or Vue) and understand the core principles behind them.

Total rewards

We believe the people building honest financial products at Affim should share in its success. That's why our total rewards are designed to support your health, growth, financial well-being,and future.

In service of our mission, we reward employees through a combination of base pay, equity (fromparent company), and comprehensive benefits.

Base pay ranges and placement within those ranges are determined based on several factors, including role, experience, and job-related skills.

In addition to base pay, all employees in this role are eligible to receive equity from the parent company each year. This means as Affim’s parent company grows, employees have the opportunity to share in that growth financially.

Equity Grade - 4 (awarded in US Dollars)

Equity grade: 4

New hire equity: $32,000-$48,000

Annual Refresh: $10,000

Reward equity: $0-$150,000

Affirm also provides flexible spending wallets to all employees for technology and wellbeing related needs, which are reimbursable up to 1390 zł per month.

In addition to your compensation, our comprehensive benefits are designed to support you and the people who matter most. Benefits include:

• Competitive paid time off, paid public holidays, and additional paid Away Days to rest and recharge.
• Comprehensive private healthcare through Lux Med's Platinum package.
• A MultiSport card to support your health and well-being.
• Learning and development programs to help you grow professionally.
• Family healthcare support through Maven and parental leave support through Parentaly.
• Mental well-being support through Lyra, including up to 12 confidential counseling or coaching sessions each year for you and your household members.
• Financial well-being support through Northstar, with unlimited access to Certified Financial Advisors and planning tools at no cost to you.
• Employee Resource Groups (ERGs) that foster connection and inclusion.
• Eligibility for creative tax benefits, subject to applicable law, role, and company policy.

Location - Remote Poland

The majority of our roles can be located anywhere in Poland.

This job description is not a contractual document, and is not intended to have binding force.

Remote-first with flexibility built inAffirm is proud to be a remote-first company. Most roles can be done from almost anywhere within the country of employment. Some positions may occasionally require in-person work at an Affim office, and a few are office-based due to the nature of the work. All new hires will be invited to attend an in-person onboarding experience.

Benefits designed for youOur benefits reflect our commitment to care, transparency, and flexibility. Here are a few highlights:

• Health coverage at no cost: We cover 100% of premiums for employees and their dependents.
• Spending stipends: Monthly stipends support your tech setup, and the ability to choose health and wellness options that are right for you.
• Time off to recharge: Flexible time off and generous holiday calendars help you rest when you need to.
• Own a piece of what you build: Our employee stock purchase plan (ESPP) lets you buy Affim stock at a discount.

We’re committed to providing an inclusive interview process, including accommodations for candidates with disabilities. If you need support, we’re happy to help.

For positions based in San Francisco or Los Angeles: Affim considers qualified applicants with arrest and conviction records, as required by law.