Senior Software Engineer, Backend (Consumer Authentication Platform)
Affirm is hiring a Senior Backend Engineer for its Consumer Authentication Platform team to design, build, and operate the secure sign-in, session, identity-federation, and step-up authentication systems serving millions of consumers across thousands of merchants. The work centers on backend systems at scale (Python/Kotlin/Java, AWS, MySQL, Kubernetes) plus auth standards like OAuth 2.0, WebAuthn/
- Compensation
- CA$153K–CA$213K / yr
- Location
- Remote Canada
- Work setup
- Remote
- Seniority
- Senior
- Employment
- Not specified
- Experience
- 4+ years
- Category
- Backend
- Posted
Skills
Must have
- 4+ years of experience designing, developing, and launching backend systems at scale using languages like Python, Kotlin, Java, or comparable
- Track record developing highly available distributed systems using AWS, MySQL, Kubernetes, relational databases, event-driven architectures, and RPC/API frameworks
- Experience defining a technical plan for delivery of a significant feature or system component with an elegant, secure, simple, and extensible design
- Proficient at making significant changes in a large codebase safely, including testing strategies, migration plans, and controlled rollouts
- Takes ownership of growth, proactively seeks feedback, and helps other engineers grow through mentorship and technical leadership
- Strong verbal and written communication skills for collaboration with global engineering and cross-functional partners
- Equivalent practical experience or a bachelor's degree in a related field
- Must reside in Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, or Saskatchewan
Nice to have
- Familiarity with OAuth 2.0, OpenID Connect, WebAuthn/passkeys, FIDO2, JWTs, and public-key cryptography
- Knowledge of security and assurance frameworks such as NIST Digital Identity Guidelines or PCI DSS
- Experience designing session-management, token-issuance, account-recovery, or multi-factor authentication systems
- Familiarity with risk-based or adaptive authentication and the interaction between identity, security, compliance, and fraud controls
Full description
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 Consumer Authentication Platform team is looking for a passionate Senior Software Engineer to help build the secure, reliable, and seamless authentication experiences that connect millions of consumers with Affirm’s financial products.
Authentication is the front door to Affirm. Our systems power critical consumer journeys (including sign-up, sign-in, account recovery, checkout authentication, step-up challenges, session management, and connected merchant experiences) across thousands of merchants and multiple countries. We build foundational capabilities such as authentication factors, identity federation, session and authorization services, and risk-based authentication that protect consumers while minimizing unnecessary friction. We work closely with Product, Security, Fraud, Identity, Analytics, Compliance, Data Science, and a wide range of engineering teams to both leverage existing systems and build new systems. This role requires a high level of technical capability, strong cross-functional communication, and a creative mindset. Our work needs to be secure, reliable, correct, scalable, and extensible. Our job is to build an authentication platform that balances security, regulatory requirements, fraud prevention, customer experience, and business growth.
As a senior engineer, you will lead significant technical initiatives, influence the architecture and evolution of the platform, and help the team deliver secure authentication capabilities that can be reused across products, merchants, and geographies.
What You’ll Do
- You will own the technical design and delivery of significant authentication platform capabilities, leading projects from early requirements and architecture through implementation, rollout, and ongoing operation.
- You will build secure, highly available systems that support consumer sign-in, authentication factors, account recovery, step-up authentication, session management, authorization, and identity federation.
- You will support your peers and stakeholders in the product development lifecycle by collaborating with product management, Security, Fraud, Compliance, design, and analytics; participating in ideation; articulating technical constraints; and partnering on decisions that properly consider risks and trade-offs.
- You will translate security, regulatory, fraud, and customer-experience requirements into pragmatic technical designs that appropriately balance risk, friction, complexity, and delivery speed.
- You will proactively identify project, process, technology, security, reliability, or business issues, advocate for them, and lead in solving them.