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

Requirements

Professional Experience

• 6 to 8 years in backend engineering with experience building shared services or platform components consumed by other teams - understanding that your customer is internal engineering is essential

• Has designed and maintained SDKs or shared libraries in production - knows what SDK stability means and has experienced the pain of breaking changes

• Experience with API gateway configuration and service mesh management in a microservices environment

• Active AI tool user - uses Cursor and Claude for development today; AI -assisted engineering is standard practice

• Platform identity: Platform identity: 'my customer is other engineers' - takes pride in developer experience, documentation quality, and SDK ergonomics

• Reliability: Reliability obsession: platform services fail twelve squads simultaneously when they go down - takes on -call, postmortems, and SLO management seriously

• AI -native: AI -native developer: Cursor and Claude open all day - models the AI -augmented engineering practice Phoenix is responsible for demonstrating

• Documentation: Documentation culture: platform code without great docs is unusable - writes runbooks, SDK guides, and ADRs as part of the definition of done

AI SDK integration design & LLM API patterns (rate limiting / fallback)  

Domain -driven design

Benefits