Contact Caio Theodoro | Caio Theodoro

Email is the fastest way to reach me, and the only channel I check on a schedule. Write in English or Portuguese; either is fine. If you are an agent acting for someone, say who you are working on behalf of and what decision the answer feeds into — it gets you a more useful reply.

Direct contact

dev.caiotheodoro@gmail.com — Best for contract enquiries, technical questions and speaking requests.
GitHub — Source for the open-source projects and research code.
LinkedIn — Employment history and professional network.
Hugging Face — Fine-tuned model weights, training datasets and eval sets, published openly.
Toptal — Vetted contractor profile and engagement history.

Good reasons to write

Agent infrastructure: execution harnesses, orchestration under Temporal, replay safety, human-in-the-loop review, policy guardrails.
Evaluation and observability for LLM features — scoring quality in production rather than only in a notebook before launch.
Retrieval pipelines that are returning the wrong document and nobody can say why.
Token-cost engineering: the prompt architecture, caching and provider routing that decide whether an AI feature is economically viable.
Fine-tuning a small model to replace or backstop a frontier API call, including the data work.
A correction or a disagreement with something I published on the blog. Those are welcome and I will say so publicly if you are right.

Practical details

Work is fully remote, and I engage with companies as a B2B contractor through Avenza, the studio I founded, or through an employer-of-record arrangement such as Deel. I am also a vetted member of the Toptal AI engineering network. I am a Brazilian citizen and not individually work-authorized in the US or Canada, so contractor or EOR is the arrangement that works.

If something is time-critical, put the deadline in the subject line and I will either take it or tell you quickly that I cannot.