Senior Software Engineer, Backend (Payments)
affirm
Remote UK
Posted May 18, 2026
- Other
- Remote
- Financial Platforms - Engineering
affirm
Remote UK
Posted May 18, 2026
Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without any hidden fees or compounding interest.
The Engineering team builds systems that power Affirm’s mission. We take pride in our craft, building reliable, performant, and scalable solutions that touch every part of the business. Whether we’re enabling new ways to pay, ensuring our platforms can scale to the most demanding levels in the industry, or developing seamless servicing experiences, our focus is on solving complex problems through exceptional engineering.
As part of the Consumer Payments team at Affirm, you'll be working on Affirm's Payment Processing Network. These systems currently process billions of dollars in payments each year and are vital components in Affirm's platform. We are looking for highly motivated software engineers who are passionate about building high throughout, high availability systems that can grow alongside a high growth business. You will be working alongside multiple partner teams across Europe and the US to support feature development, international expansion as well as moving the dial on key financial metrics for the business.
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 help develop talent on your team by providing feedback and guidance, and leading by example.
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.
Base Pay Grade - N
Equity Grade - 5
Employees new to Affirm typically come in at the start of the pay range. Affirm focuses on providing a simple and transparent pay structure which is based on a variety of factors, including location, experience and job-related skills.
Base pay is part of a total compensation package that may include equity rewards, monthly stipends for health, wellness and tech spending, and benefits (including 100% subsidised medical coverage, dental and vision for you and your dependents.)
Base pay range per year: £120,000 - £168,000
Location: UK Remote
#LI-Remote
Affirm is proud to be a remote-first company! The majority of our roles are remote and you can work almost anywhere within the country of employment. Affirmers in proximal roles have the flexibility to work remotely, but will occasionally be required to work out of their assigned Affirm office. A limited number of roles remain office-based due to the nature of their job responsibilities.
We’re extremely proud to offer competitive benefits that are anchored to our core value of people come first. Some key highlights of our benefits package include:
We believe It’s On Us to provide an inclusive interview experience for all, including people with disabilities. We are happy to provide reasonable accommodations to candidates in need of individualized support during the hiring process.
[For U.S. positions that could be performed in Los Angeles or San Francisco] Pursuant to the San Francisco Fair Chance Ordinance and Los Angeles Fair Chance Initiative for Hiring Ordinance, Affirm will consider for employment qualified applicants with arrest and conviction records.
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