Greenhouse ·
full-timeSenior Software Engineer, Backend (partner Merchant Interface)
Affirm · Remote US
Affirm provides a transparent pay‑over‑time service that lets consumers split purchases into fixed installments without hidden fees. The Partner Merchant Interfaces – Integration team builds and maintains the APIs that external partners and merchants use to connect to Affirm’s platform, supporting high‑volume integrations such as those with Amazon and Stripe. As a Senior Software Engineer on this backend‑focused team, you will design, develop, and launch scalable services, write clean, well‑tested code in Python or Kotlin, and work with AWS, MySQL and Kubernetes to keep the integration layer reliable. Daily tasks include collaborating with product and engineering stakeholders, reviewing code, debugging production issues, and balancing speed with quality to meet business goals while protecting system uptime. The role suits engineers with backend experience at scale, familiarity with distributed‑systems concepts, and strong communication skills who enjoy owning their growth through feedback and mentorship. Affirm offers remote‑first work, health‑coverage subsidies, monthly tech and wellness stipends, flexible time off, and an employee stock purchase plan.
At Affirm, 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. The Partner Merchant Interfaces - Integration team within Decisions Foundations is growing and we are looking for a Software Engineer. You will be part of a fast paced team which is responsible for the APIs that Partners and Merchants use to integrate with Affirm, and also power some of our top partners like Amazon and Stripe. What You'll Do · With the support of your team, you will work on tasks that contribute to the team's projects and goals. · You will work collaboratively and proactively with your team and stakeholders, bringing them along for your work and helping to create visibility and dialog regarding the risks and trade-offs related to your work. · You will strike the right balance of speed and quality in your work, ensuring that we hit our business goals while protecting our systems from downtime. · You will contribute to a sense of community on your team by engaging in growth and development activities. What We Look For · You have previous work or internship experience designing, developing and launching backend systems at scale and are experienced using one of Python or Kotlin. · You are familiar with the building blocks of distributed systems, and the technologies like AWS, MySQL and Kubernetes. · You have mastered taking a simple problem or business scenario into a solution that interacts with multiple software components, and executing on it by writing clear, easily understood, well tested and extensible code. · You are comfortable navigating a large code base, debugging others' code, and providing feedback to other engineers through code reviews. · 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. Base Pay Grade - N Equity Grade - 9 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% subsidized medical coverage, dental and vision for you and your dependents.) USA base pay range (CA, WA, NY, NJ, CT) per year: $195,000 - $255,000 USA base pay range (all other U.S. states) per year: $173,000 - $233,000 LI-Remote Remote-first with flexibility built in Affirm 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 Affirm 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 you Our 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 Affirm 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: Affirm considers qualified applicants with arrest and conviction records, as required by law. By clicking "Submit Application," you acknowledge that you have read Affirm's Global Candidate Privacy Notice and consent to the use of your personal information as described.
| Role | Senior Software Engineer, Backend (partner Merchant Interface) |
|---|---|
| Company | Affirm |
| Location | Remote US |
| Compensation | Not disclosed |
| Posted | 2026-09-09 |
| Deadline | Rolling |
Typical process for this type of role
A general guide — the exact steps for this specific listing may vary; check the original posting for details.
- 1ApplicationSubmit your resume through the apply link.
- 2ScreeningRecruiter reviews your background against the role.
- 3AssessmentA technical test, assignment, or coding round, depending on the role.
- 4Interview(s)One or more rounds with the hiring team.
- 5OfferOffer letter with compensation and start date.
Before you apply
0/4Senior Software Engineer, Backend (partner Merchant Interface) at Affirm: frequently asked questions
- What is the salary for this role?
- Affirm has not stated compensation in the listing. Check the original posting or ask during the application process.
- Is the Senior Software Engineer, Backend (partner Merchant Interface) position remote, hybrid or onsite?
- The listing marks this role as remote, with Remote US as the location.
- What is the application deadline?
- Affirm has not listed a fixed deadline, so apply early in case the opening is filled.
- How do I apply for the Senior Software Engineer, Backend (partner Merchant Interface) role?
- Use the Apply button on this page. It opens the original listing on job-boards.greenhouse.io, where you submit your application with the company.
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