Senior Software Engineer, Backend – Consumer Authentication Platform

Affirm

. Own technical design and delivery of significant authentication platform capabilities from requirements and architecture through implementation, rollout, and ongoing operation .

Posted 9/23/2026full-timeRemote • CanadaSenior💰 CA$153,000 - CA$213,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in designing and delivering secure, highly available authentication systems, with proficiency in backend development and a strong understanding of security and compliance standards. Capable of mentoring engineers and effectively communicating technical concepts to diverse audiences.

Highest-signal resume keywords

Backend System DesignPython ProgrammingAWS Cloud ServicesOAuth 2.0 FamiliarityMulti-Factor Authentication Systems

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

Backend DevelopmentDistributed SystemsKotlin ProgrammingJava ProgrammingRelational DatabasesEvent-Driven ArchitecturesAPI FrameworksSession ManagementToken-IssuancePublic-Key Cryptography

Soft Skills

Strong Communication SkillsMentoring

Tools & Technologies

MySQLKubernetes

Industry Keywords

NIST Digital Identity GuidelinesPCI DSSRisk-Based AuthenticationFraud Controls

Tech Stack

Tools & technologies

AWSDistributed SystemsJavaKotlinKubernetesMySQLPython

About the role

Key responsibilities & impact

Own technical design and delivery of significant authentication platform capabilities from requirements and architecture through implementation, rollout, and ongoing operation
Build secure, highly available systems for sign-in, authentication factors, account recovery, step-up authentication, session management, authorization, and identity federation
Collaborate with product management, Security, Fraud, Compliance, design, and analytics teams
Translate security, regulatory, fraud, and customer-experience requirements into pragmatic technical designs
Identify and solve project, process, technology, security, reliability, and business issues
Create and monitor operational metrics, escalate issues, and support on-call efforts
Establish and improve code review and design standards
Mentor engineers through design reviews, feedback, and hands-on collaboration
Communicate technical decisions, constraints, risks, and trade-offs to technical and non-technical audiences
Lead investigations of complex production issues and identify systemic improvements

Requirements

What you’ll need

4+ years of experience designing, developing, and launching backend systems at scale
Experience with Python, Kotlin, Java, or another comparable modern programming language
Experience developing highly available distributed systems
Experience with AWS, MySQL, Kubernetes, relational databases, event-driven architectures, and RPC or API frameworks
Experience defining technical plans for significant features or system components
Proficiency making significant changes in large codebases, including testing strategies, migration plans, and controlled rollouts
Strong verbal and written communication skills
Equivalent practical experience or a bachelor’s degree in a related field
Familiarity with OAuth 2.0, OpenID Connect, WebAuthn/passkeys, FIDO2, JWTs, and public-key cryptography
Knowledge of 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 identity, security, compliance, and fraud controls

Benefits

Comp & perks

100% subsidized medical coverage for employees and dependents
Dental and vision coverage for employees and dependents
Monthly stipends for tech setup
Monthly health and wellness spending stipends
Flexible time off
Generous holiday calendars
Employee stock purchase plan (ESPP) with discounted Affirm stock
Inclusive interview process and accommodations for candidates with disabilities
In-person onboarding experience