Principal Identity And API Architect (IAM)

TL;DR

Principal Identity And API Architect (IAM): Designing and owning the end-to-end identity platform and API security strategy for a programmatic advertising marketplace with an accent on multi-tenant authorization and secure authentication. Focus on implementing ReBAC systems, optimizing Auth0 tenant architecture, and governing API gateways to handle billions of transactions.

Location: London, United Kingdom

Salary: €90,000 - €130,000

Company

hirify.global is an advertising platform on a mission to elevate digital advertising through beautiful creative, quality publishers, actionable data and smart targeting.

What you will do

• Architect and own the end-to-end identity platform, including tenant models, SSO integrations, and machine-to-machine authentication.
• Design and implement Auth0 tenant architecture, including custom domains, enterprise connections, and token lifecycle management.
• Build and operate multi-tenant authorization models using OpenFGA or comparable ReBAC systems (e.g., SpiceDB, Ory Keto).
• Own the API gateway layer, designing rate limiting, scoped token validation, and mTLS enforcement across Traefik, Kong, or AWS API Gateway.
• Lead identity integrations for both publisher-side (SAML 2.0, OIDC) and demand-side (DSP and agency API authentication).
• Manage AWS identity and API infrastructure, including IAM roles, Cognito integration, and Secrets Manager.

Requirements

• 8+ years of software engineering or platform architecture experience.
• 4+ years focused on identity, IAM, or API security.
• 2+ years of hands-on production experience with Okta's Auth0.
• Deep fluency in OAuth 2.0, OpenID Connect, SAML 2.0, JWT, and JWKS.
• Experience designing and operating API gateway layers at scale.
• Proficiency in at least one backend language (Go, Java, or Python preferred).

Culture & Benefits

• Medical, Dental & Vision Plans.
• Flexible PTO.
• 401k with employer match.
• Positive, collaborative, and compassionate work environment focused on continuous innovation.