Backend Engineer II, Partner Identity & Access (Auth0)

Booking.com; Amsterdam; Hybrid; EUR 110,000 - 140,000; Full time

Benefits offered by this job

Annual leave and paid time off

Hybrid working arrangements

Discounts on Booking.com products

Job summary

Booking.com is hiring for a senior backend engineer to own and operate production CIAM services across partner authentication. You will migrate legacy Perl systems to Auth0 while maintaining live traffic and ensuring no downtime for partners.

You’ll work on authentication workflows, token design, and collaboration with teams across the identity platform. The role emphasizes reliability, incident response, and strong English communication.

Qualifications

• Experience building production CIAM systems for external users.
• Hands-on with Auth0 in production environments.
• Migration experience between identity providers on live traffic.
• Working with legacy Perl codebases in production.

Responsibilities

• Build and operate backend services across partner authentication.
• Lead migration workstreams from Perl to Auth0 with phased rollouts.
• Maintain and evolve the legacy authentication estate to reduce dependency.
• Configure identity platform with authentication and authorization logic in Auth0.
• Lead technical investigations for login-path incidents and anomalies.
• Measure login health through instrumentation and controlled experiments.
• Support partners and engineers as the go-to technical reference for identity.
• Participate in on-call duties with a direct partner-visible blast radius.

Skills

Backend engineering

CIAM

Auth0

OAuth 2.0 / OIDC

Java

Perl

Tools

Auth0

JWT

Job description

Booking.com is hiring for a senior backend engineer to own and operate production CIAM services across partner authentication. You will migrate legacy Perl systems to Auth0 while maintaining live traffic and ensuring no downtime for partners.

You’ll work on authentication workflows, token design, and collaboration with teams across the identity platform. The role emphasizes reliability, incident response, and strong English communication.