Senior Software Engineer - Authorisation

Are you an enthusiastic Software Engineer who’s ready to embark on new challenges and take your career to new heights? Join our team at Enigma in Helsinki as a Senior Software Engineer , and play a pivotal role in building our secure and scalable Identity and Access Management system. About the Team: As part of the Infrastructure Group at Smartly, Enigma builds and operates the systems that govern access across our SaaS platform. The team focuses primarily on authorisation : determining what users, teams, services and customers are allowed to access, and enforcing those decisions reliably across a complex, distributed product. We solve challenging problems around: Fine-grained authorisation across platform modules and customer environments. Role-Based Access Control (RBAC) and permission modelling. Policy design, evaluation and enforcement. Service-to-service access and delegated permissions. Scalable access-control systems for multi-tenant SaaS. Auditable and observable authorisation decisions. Supporting identity and authentication signals where they are required for access decisions. Billing operations and the Billing Engine. Authentication and login technologies, including Single Sign-On (SSO), SAML and OpenID, are relevant to the wider domain but are not the primary focus of this position. The main focus is building robust authorisation capabilities on top of identity and authentication signals. We develop and maintain microservices built mainly using TypeScript, NodeJS, Koa, KnexJS, Postgres and Kafka , running in our Kubernetes clusters. This role is focused on the authorisation domain within the Enigma team. Check out our Engineering at Smartly site to learn how our engineering and product development work. As a Senior Software Engineer, You Will: Architect, design and document scalable authorisation systems for complex, distributed and multi-tenant environments Design permission models, access-control policies and evaluation flows that can be applied consistently across Smartly’s platform Build and maintain services responsible for making and enforcing access decisions across multiple products and modules. Translate architectural designs into maintainable, robust and high-quality code, primarily using NodeJS and TypeScript . Develop APIs and service integrations that enable other backend services and frontend applications to consume authorisation capabilities. Consider consistency, performance, availability, security and auditability when designing authorisation systems. Establish patterns and best practices for integrating access checks into services across the wider platform. Improve the observability, testing and operational reliability of authorisation decisions. Collaborate with Product, Infrastructure, Security, Engineering and Support teams to translate business and customer requirements into viable access-control solutions. Mentor other engineers and contribute to engineering standards, technical design reviews and ways of working. Help shape the future architecture of Smartly’s authorisation platform. What We’re Looking For: At least 5 years of experience designing, architecting and building robust, complex and distributed web applications, with system-level design as a core responsibility. Strong experience designing and implementing authorisation, access-control or permission systems in production. A clear understanding of concepts such as: RBAC and permission modelling. Policy-based access control. Fine-grained or resource-level permissions. Multi-tenant access control. Service-to-service authorisation. Delegation and impersonation. Policy evaluation, enforcement and auditing. Strong backend development skills with NodeJS and TypeScript . Professional experience selecting, documenting and applying architectural and design patterns. Experience building APIs and distribu