Senior Backend Engineer Go (Identity & Access Management)

Andersen is a global software development company with over 18 years of experience supporting businesses worldwide in digital transformation. Headquartered in Poland, they operate development centers across Germany, the USA, the UK, Lithuania, Hungary, Kazakhstan, Georgia, Azerbaijan, Cyprus, and the UAE. They offer end-to-end IT services including custom software development, API integration, system architecture, legacy modernization, and long-term support, with expertise in AI, Machine Learning, Data Science, Big Data, and Visual Technologies.

• Experience in backend engineering for 7+ years, including 5+ years with Go.
• Experience working with IAM in production environments.
• Strong production experience with Go and gRPC, building complex, distributed backend systems.
• Deep expertise in authentication and authorization, including OAuth 2.0, OIDC, SSO, MFA, RBAC, JWT signing/verification/assertions, token security, session management, and cryptography.
• Strong understanding of web security, federated identity, secure coding, and OWASP Top 10.
• Hands-on experience with cloud platforms (AWS preferred), container orchestration (Kubernetes), and Infrastructure as Code (Terraform, Terragrunt, OpenTofu/Tofu).
• Experience designing high-throughput, low-latency systems with a focus on security and correctness.
• Strong communication skills and ability to explain security and architecture trade-offs to technical and non-technical stakeholders.
• Level of English – from Upper-Intermediate and above.

Nice to have:

• Experience with SAML, SCIM, PKI, JWKs/JWKS endpoints, key management (KMS/HSM) and token introspection.
• Working knowledge of identity platforms (commercial or open source), rate limiting, abuse mitigation, and adaptive authentication.

• Designing, developing, and operating high-throughput, low-latency identity services: Single Sign-On (SSO), Multi-Factor Authentication (MFA), session management, and federation.
• Implementing and scaling modern authentication and authorization protocols and token formats (OAuth 2.0, OpenID Connect, JWTs), including secure token issuance, rotation, and revocation strategies.
• Designing idiomatic, testable code and clear API contracts (gRPC/HTTP).
• Using DevOps experience to deploy, manage, and automate identity infrastructure (CI/CD, monitoring, and incident response).
• Integrating and maintaining solutions with custom and standard identity providers (e.g. Keycloak and AWS Cognito), and federation patterns.