Case Study
Carrier HVAC — Building the Engineering Team Behind a Global IoT SaaS Platform
Carrier HVAC
Role
Fractional Director of Cloud Architecture — IoT SaaS Platform
Period
June 2021 – November 2023
Duration
29 months
Reporting Line
Dual reporting — VP (Technology) and VP (Business)
Industry
Connected HVAC / Smart Buildings
The Situation
Carrier HVAC was investing in a global IoT SaaS platform as a strategic digital transformation play — building the connected-buildings capability that would let large enterprise customers deploy sensors and controllers across their facilities to monitor air temperature and air quality at scale.
The customers weren't small: stadiums (Atlanta Braves), enterprise data centers (AWS), and other large-facility operators with sensors deployed per floor and per section, generating millions of data points daily that the platform needed to ingest, process, and surface back to operators.
Carrier was hiring and promoting from within to staff the team — a strategic decision that built loyalty and institutional knowledge, but meant those internal hires needed senior architectural mentorship to rise into the level of work the platform demanded.
Why a Fractional Executive
Carrier didn't need a permanent VP to displace the leadership they were promoting from within. They needed a senior architectural and engineering leader embedded alongside the team — mentoring the people they were elevating while owning the platform architecture, the program management, and the dual-stakeholder coordination between technology and business leadership.
What I Led
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Built and led the engineering team. Grew a 15-person team across frontend, backend, and DevOps. Established career development paths, pair programming culture, and an architectural review board.
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Architected the platform. Event-driven, serverless IoT SaaS using AWS IoT Core, Kinesis, Lambda, Step Functions, and API Gateway — scaling elastically to ingest millions of device events daily with sub-second latency.
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Designed the GraphQL API layer behind API Gateway, reducing client API calls by 60% through efficient query design and batch processing.
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Designed polyglot persistence. Selected purpose-built databases for each workload type — DynamoDB for high-velocity device state, Timestream for time-series telemetry, Neptune for device relationship graphs, MongoDB for flexible documents.
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Established Infrastructure as Code. AWS CDK (TypeScript) with reusable construct patterns adopted across services.
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Built B2B identity and security architecture integrating Okta SSO with API security patterns for the multi-tenant platform.
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Designed data ingestion foundations (Kinesis → Lambda → S3) establishing the basis for future ML and predictive analytics on IoT telemetry.
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Owned cost engineering. Lifecycle policies, capacity planning, and Lambda memory optimization delivered 40% infrastructure cost reduction.
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Bridged technology and business leadership. Reporting into both a tech VP and a business VP, aligned cross-functional priorities and translated architectural decisions into business impact.
Business Outcomes
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99.9% uptime on a global IoT SaaS platform serving 50,000+ B2B users
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40% infrastructure cost reduction while supporting millions of daily device events
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50% reduction in time-to-market through serverless architecture and IaC automation
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Enabled a new IoT SaaS revenue stream for Carrier's connected-HVAC strategy
What I Left Behind
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A 15-person engineering team with established career paths, pair programming culture, and architectural review discipline
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A production IoT SaaS platform serving 50,000+ B2B users at 99.9% uptime
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Documented serverless architecture patterns and reusable CDK constructs
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A data foundation ready for future ML and predictive analytics