Senior Backend Engineer - Platform engineering

About the role

Phoenix is the platform engineering squad - the team responsible for the shared backend infrastructure that all squads build on. API gateway, service mesh, shared platform services, the AI SDK integration layer, and the IAM/RBAC SDK are all Phoenix territory.

Senior Backend Engineers on Phoenix are building the surfaces other engineers use. Your customer is not the end borrower - it is the 12 squads that depend on Phoenix's APIs, SDKs, and shared services to build their features. Platform engineering is a product discipline, and the quality of what you build determines the velocity of the entire engineering organisation.

Key Responsibilities

Platform Service Development

• Build and maintain the shared backend platform services - the IAM/RBAC SDK, the AI SDK wrapper, the notification service, the event bus, and the feature flag system that every squad consumes

• Own the IAM/RBAC SDK implementation - translating the Cloud-Native Platform Architect's design into a production-ready SDK that twelve squads can integrate with confidence

• Build the AI SDK integration layer - the secure, consistent interface for squads to call LLM APIs with rate limiting, cost tracking, PII redaction, and fallback handling built in

• Design and implement the shared event bus patterns - how domain events are published, subscribed to, and replayed across services using SQS or Kafka

• Write the platform SDK documentation and integration guides that product squad engineers use to onboard themselves without requiring Phoenix involvement

API Gateway & Service Mesh

• Own the API gateway implementation - routing configuration, authentication enforcement, rate limiting rules, and the observability instrumentation that feeds into the platform monitoring stack

• Implement service mesh configuration for inter-service communication - mTLS, circuit breakers, retry policies, and traffic management for the twelve-service landscape

• Define and enforce API standards in collaboration with the Cloud-Native Platform Architect - contract-first development, OpenAPI spec, versioning, and backward compatibility discipline

• Build the API testing infrastructure - consumer-driven contract tests that catch breaking changes before deployment and give squads confidence in the API gateway configuration

AI-Native Platform Engineering

• Use Cursor and Claude as primary development tools - the Phoenix engineering standard is AI-augmented development; all code, tests, and documentation are AI-assisted

• Build the n8n and AppSmith integration hooks - the platform-level API endpoints and webhooks that allow Rangers' automations to interact safely with platform services

• Implement observability instrumentation across platform services - distributed tracing (OpenTelemetry), structured logging, and metrics that give the organisation visibility into platform health

Quality, Reliability & Mentoring

• Set and maintain code quality standards within Phoenix - code review, refactoring discipline, test coverage, and the mentoring of Intermediate and Associate engineers

• Own platform service reliability - SLO monitoring, incident response, and the postmortem process when platform services affect product squad delivery

• Contribute to the Platform Guild - share platform engineering knowledge, present implementation decisions, and participate in cross-squad technical discussions