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Portrait of AJ Welch

Hi, I'm AJ.

I've been a software and data engineer for over 15 years at:

Google

Google Cloud. BigQuery. Clients:
Palo Alto
Verizon
Boeing

CompilerWorks

Acquired by Google. Clients:
PayPal
MLB
OfferUp

Chartio

YC S10. Acquired by Atlassian. Clients:
Reddit
Duolingo
Lyft

I work with small data teams at companies with fewer than 500 employees. In particular, I've been helping teams use DSPy and GEPA to optimize both the AI and data platform layers of their stack.

More broadly, I focus on:

AI

  • Agents, workflows and automation
  • Context engineering and RAG
  • Optimization and fine-tuning
  • Evals and dataset engineering
  • Observability, guardrails and cost control

Data

  • Semantic layer models and analytics
  • Pipeline orchestration and ELT/ETL
  • Ingestion, integration and streaming
  • Performance and cost optimization
  • Observability, data quality and governance

If you're interested in working together, please feel free to email me or book a call. Retainers start at $15k for 80 hours a month.

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