Senior Software Engineer, Data Platform

iFIT is a company focused on creating a comprehensive health and fitness platform that integrates various elements of health into an interactive experience. They are seeking a Senior Software Engineer for their Data Platform team, responsible for building backend systems and data pipelines to enhance user engagement and deliver personalized fitness experiences. The role involves leading initiatives, ensuring data reliability, and integrating AI into the engineering practices.

Responsibilities:

• Own critical systems as the primary, accountable owner — including ingestion, aggregation, streaming, integrations, and content delivery — including their long-term health, performance, and evolution
• Lead large, multi-milestone initiatives from design through delivery: break complex work down for others, remove technical bottlenecks, and deliver predictably under complexity
• Produce durable, defensible architecture, making cost, reliability, and maintainability first-class constraints and anticipating the multi-year impact of your decisions
• Build AI into how the team works and what it ships, driving AI-augmented engineering practices and identifying high-value places to build AI-powered systems and tooling
• Own reliability and operations: define SLOs, observability, and alerting; eliminate recurring incidents; reduce toil; and build systems that don't depend on heroics. Participate in on-call for the services you own
• Design, provision, and operate your own infrastructure on AWS, including Lambda/Serverless, ECS Fargate, MSK/Kafka, RDS/Postgres, MongoDB, S3, and Kinesis, managed as code with Terraform
• Protect data correctness through strong schema, versioning, and API-contract discipline, so member activity data is accurate and trustworthy across every consumer
• Raise the bar on code quality and testing, write design docs that align multiple stakeholders, and act as an escalation point for technical decisions
• Partner closely with mobile, web, and equipment teams to design clean, debuggable client-facing contracts

Requirements:

• 5+ years of experience building and operating production backend services
• Deep proficiency in Node.js and TypeScript, with strong fundamentals in API design (REST/GraphQL) and service architecture
• Hands-on AI development experience — building with modern AI tooling and incorporating AI/LLM capabilities into real systems, and using AI to materially accelerate your own engineering
• Proven ownership of data-intensive or event-driven systems, including streaming, ingestion pipelines, time-series or aggregation workloads, or high-throughput integrations
• Experience operating systems on AWS, including Lambda, ECS, S3, RDS/Postgres, MongoDB, and a streaming/messaging layer such as Kafka/MSK, Kinesis, or SNS/SQS, and managing infrastructure as code with Terraform
• A track record of reliability ownership, including SLOs, monitoring, incident response, and postmortems that actually reduce recurrence
• Strong design and written communication skills — you can frame ambiguous problems, document tradeoffs clearly, and align stakeholders
• A member-first mindset: you reason about technical decisions in terms of athlete impact and treat member-data trust as something to protect structurally
• Authorized to work in the United States without sponsorship
• NestJS and/or the Serverless framework experience
• Experience building agentic AI systems, developer tooling, or AI-powered product features at scale
• Experience with Kafka Streams or stream-processing frameworks
• IoT/MQTT or real-time, low-latency systems experience
• Experience integrating third-party fitness and health platforms such as Strava, Garmin, Apple Health, Google Fit, or Terra
• Familiarity with the fitness, health, or wearables domain