Data Engineering · AI Agents · Architecture

From raw data to intelligent agents — designed end to end.

Sefermark designs, builds, and ships the complete data and AI product — pipelines, schemas, orchestration, and agentic AI systems that reason over live warehouse data. Snowflake-centric, cloud-agnostic, Azure-fluent.

✦ SnowPro SME SnowPro Advanced: Data Architect SnowPro Advanced: Data Engineer SnowPro Core Azure AI Engineer
What We Do

End-to-end, from first ingest to shipped product

Most vendors hand you a diagram and leave. We work across the full lifecycle — designing the architecture, building the pipelines, and staying through deployment so what we design actually ships.

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Data Pipelines & Orchestration

Reliable, observable ELT built on Snowflake — Snowpipe, Streams & Tasks, Dynamic Tables — orchestrated with the tool that fits your team.

  • Batch & streaming ingestion
  • Dynamic Tables & automated testing
  • Airflow / Dagster / ADF orchestration
  • Pipeline rescue & cost tuning
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Schema & Data Architecture

Schemas that survive contact with the business. Dimensional, Data Vault, or wide — chosen for your query patterns, not fashion.

  • Warehouse & lakehouse design
  • Medallion layering done right
  • Data contracts & governance
  • Snowflake RBAC & cost architecture
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AI Systems & Agent Workflows

Agents that reason over live warehouse data, call tools, and take action — grounded in governance, not duct-taped to the side of your stack.

  • Multi-agent orchestration & pipelines
  • RAG & Cortex AI on Snowflake
  • Azure OpenAI / AI Foundry integration
  • LLM evaluation, guardrails & observability
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Streamlit Apps & Human-in-the-Loop

Streamlit apps that go beyond dashboards — they write back to the database, put humans inside AI workflows, and turn your warehouse into an operational system.

  • Human-in-the-loop AI review & approval UIs
  • Writeback apps: update, label, approve records
  • Snowflake-native Streamlit & standalone deploys
  • Internal ops tools & AI copilots
Live Demo

Interactive geospatial analytics

A taste of what modern data tooling can do — a fully interactive 3D city map running on open data (OpenStreetMap), rendered live in your browser. The same techniques power geospatial analytics in Snowflake with GEOGRAPHY types, H3 indexing, and Streamlit apps.

Built with MapLibre GL JS + OpenFreeMap vector tiles (OpenStreetMap data). Click and drag to pan, right-click-drag to rotate, scroll to zoom. Buildings extrude in 3D at street zoom levels.

Architecture Patterns

Patterns we design and build

Every engagement starts with the right pattern for your data shape, latency needs, and team. Here are four we implement most often — all Snowflake-centric, all cloud-agnostic.

Sources SaaS · DBs · Files Bronze Raw, immutable Silver Cleansed, conformed Gold Business marts Snowflake · Dynamic Tables · Snowpark Python BI · Data Apps · ML Features · Reverse ETL

Medallion ELT on Snowflake

Land raw data in Bronze untouched, conform and test it in Silver, and serve business-ready marts from Gold. Implemented with Dynamic Tables or Snowpark Python so every layer is versioned, tested, and rebuildable from raw.

When it fits: analytics platforms, multi-source consolidation, teams that need auditability and the ability to replay history.

Events / IoT CDC (DBs) Files / Blob Kafka / Event Hubs + Snowpipe Streaming Snowflake Streams & Tasks Dynamic Tables < 1 min latency Live Apps

Near-Real-Time Streaming Ingest

Events, CDC feeds, and file drops flow through Kafka or Azure Event Hubs into Snowflake via Snowpipe Streaming, with Streams & Tasks or Dynamic Tables transforming continuously. Minute-level freshness without managing Spark clusters.

When it fits: operational dashboards, fraud/anomaly detection, IoT telemetry, CDC replication from transactional systems.

Docs + Tables governed data Cortex Search embeddings + hybrid LLM Layer Cortex / Azure OpenAI Apps & Agents Evaluation · Guardrails · RBAC · Observability AI runs where the data lives — no copies, full governance

Enterprise AI / RAG Architecture

Retrieval-augmented generation grounded in your governed warehouse: Cortex Search over documents and structured data, an LLM layer (Snowflake Cortex or Azure OpenAI), and an evaluation + guardrail loop so quality is measured, not assumed. Row-level security carries straight through to AI answers.

When it fits: internal knowledge assistants, analyst copilots, customer-facing AI grounded in your data, the retrieval backbone for agentic systems.

User / Trigger Orchestrator Agent plan · route · decide · loop SQL Tool Snowflake · Cortex Analyst Search Tool Cortex Search · RAG Action Tool APIs · alerts · webhooks Result / Action Agentic loop: observe → plan → tool call → repeat

Agentic Workflows on Your Data

An orchestrator agent breaks a goal into steps, calls tools — SQL against Snowflake, Cortex Search for RAG retrieval, external APIs for action — and loops until the task is done. The result is an AI system that reasons over live warehouse data, not static snapshots.

When it fits: analyst copilots, automated data quality pipelines, pipeline monitoring & self-healing, customer-facing AI that acts — not just answers.

AI Model / Agent Output Streamlit Review App approve · edit · reject · flag full context, one click to act 👤 Human reviewer / operator Snowflake Write decision logged · pipeline triggered

Streamlit as the Human-in-the-Loop Layer

Streamlit apps aren't read-only dashboards — they're the interface where humans step inside AI workflows. An agent generates a prediction or draft; the operator reviews it in a purpose-built Streamlit UI; approval or correction writes back directly to Snowflake and triggers the next step downstream.

When it fits: AI output review & approval queues, data labeling & annotation, model-assisted data correction, any workflow where a human decision needs to enter the database cleanly.

Tooling

The stack we work in

Snowflake at the center, with best-of-breed tools around it. We recommend what fits your team and budget — including replacing tools you're overpaying for.

Snowflake
Data platform, Cortex AI, Snowpark, Streamlit
Microsoft Azure
ADF, ADLS, Functions, Event Hubs, Azure OpenAI
Snowflake Cortex
Cortex AI, Cortex Search, Cortex Analyst, Cortex Guard
Python
Pipelines, Snowpark, APIs, ML
Streamlit
Writeback apps, human-in-the-loop UIs, AI copilots, Snowflake-native & standalone
Fivetran / Airbyte
Managed connector ingestion
Kafka / Event Hubs
Streaming & CDC backbone
Power BI / Tableau
BI & semantic layers
Azure OpenAI / OpenAI
LLMs, embeddings, agents
GitHub Actions / Azure DevOps
CI/CD for data & AI
About Our Founder

Jonathan Kelly

Jonathan Kelly is a data engineer and architect who builds on Snowflake every day. Over [X] years he has designed and shipped data platforms, pipelines, and AI systems for [industries/companies — placeholder], working across the full stack from ingestion to the dashboards and AI apps executives actually use.

Jonathan holds the SnowPro SME distinction — awarded to a small group of subject-matter experts who help author and review Snowflake's own certification exams — alongside both SnowPro Advanced certifications and Microsoft's Azure AI Engineer certification. Snowflake is his specialty; Azure is his home cloud; the architecture is always cloud-agnostic.

His approach: understand the business problem first, design the simplest architecture that solves it, build it with your team so they can run it without him, and stay accountable until it's live in production.

SnowPro Subject Matter Expert (SME)
Snowflake — invited expert; contributes to Snowflake's certification program
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SnowPro Advanced: Data Architect
Snowflake
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SnowPro Advanced: Data Engineer
Snowflake
SnowPro Core
Snowflake
Azure AI Engineer Associate
Microsoft
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