Talk
Semantic layers promise a single source of truth for metrics, but actually building one reveals a
tangle of technical and organizational challenges. In this talk, I'll share my ongoing journey
constructing a semantic layer using MetricFlow, dbt, and Snowflake in a multi-tenant data warehouse
- and the surprising role AI agents played along the way.
I'll cover three phases. First, agents as builders: how I used AI agents equipped with custom
validation tools to accelerate the build process. These agents helped catch metric definition
conflicts, validate grain mismatches like fan-out joins, and surface hidden assumptions about schema
design. I'll show how running parallel agents with the right tooling turned data migration and
validation from a bottleneck into a manageable workflow.
Second, agents as consumers: once a semantic layer exists, it becomes a governed API that agents can
query with confidence. I'll demonstrate how a well-structured semantic layer lets agents understand
business context - asking "what was revenue last quarter?" and getting trustworthy answers instead
of hallucinations.
Third, the honest part: open questions I'm still grappling with. Who should own metric definitions -
data engineers, analysts, or domain experts? How do you model the underlying schema to support both
human and agent consumers? Which tools actually fit your use case? These aren't solved problems, and
I'll share where I am in figuring them out.
This talk is for data engineers, analytics engineers, and anyone curious about how semantic layers
and AI agents intersect. You'll leave with practical MetricFlow patterns, lessons from real
validation tooling, and a realistic picture of what it takes to build governed data infrastructure
with AI as a collaborator.
About the Speaker
I am a Staff Data Platform Engineer at ServiceTitan, with more than 10 years of experience in data engineering. I have a scientific background - I started my career as a biophysicist, which shaped how I think about data systems and problem-solving. Throughout my career I have mostly built data analytical platforms across companies of different scales, from early-stage startups to Big Tech. I also teach an introductory course on data engineering in the ASDS master's program at YSU, something I have been doing for almost seven years now and genuinely enjoy sharing with the next generation of engineers.